Skip to main content

Awadallah Dafaallah

University Of Gezira, Department of Crop Protection, Faculty Member

Followers

556

Following

66

Co-author

1

Public Views

Crop Protectionist (Weed Science).
Botanist .
Statistician.
Expert in postgraduate curricula and programs.
Certified Instructor, Canadian Academy for Training and Development.
Certified Instructor, Arab Board for Human Development.
Certified Instructor, University of Gezira.
Phone: + 249092295166 ; + 249111992213
Address: Department of Crop Protection, Faculty of Agricultural Sciences, University of Gezira, P. O. Box 20, Wad Medani, Sudan

less

Uploads

Papers by Awadallah Dafaallah

Association of Aquatic Weed Abundance and Water Quality, Gezira Scheme Canals, Sudan

Journal of Research in Weed Science, 2023

Water weeds are notorious for causing various troubles. Gezira Scheme in Sudan is being choked by... more Water weeds are notorious for causing various troubles. Gezira Scheme in Sudan is being choked by the increasing proliferation of aquatic weeds. This study aimed to look at the association between aquatic weed abundance and water quality in some canals in Sudan's Gezira Scheme in the year 2018. The study area included 18 sites, i.e. 6 canals classified into 3 parts (beginning, middle, and end). The abundance of aquatic weed species was evaluated visually at each site using a scale of (0-5), and water quality was examined by assessing physical, chemical, and biological properties. Descriptive statistics and variance analysis were used to analyze the data. The findings revealed that community structure was comprised of significant changes in the abundance of aquatic weed species throughout the year, as follows: floating (1.7-2.1), emergent (0.2-0.3), submergent (0.3), and bank aquatic weeds (1.5-2.2). In winter and summer, the most abundant species were Vossia cuspidata (4.0) and Cynodon dactylon (3.0-3.7). Temperature and turbidity were shown to be the most critical elements in restricting the development and abundance of aquatic weeds, along with alkalinity, salinity, and nutrients. The canals are habitat to a diverse range of living organisms, including animals, bacteria, fungi, and algae, which indicates the water's appropriateness for the presence and development of aquatic weeds. All of these insights will be valuable in the management of aquatic weeds in Gezira scheme's canals.

Efficacy and Selectivity of S-Metolachlor for Weed Control in Sugar Beet (Beta vulgarisL.), Gezira State, Sudan

Sudan University of Science and Technology, Dec 1, 2020

Curriculum vitae -Prof. Dr. Awadallah Belal Dafaallah

Curriculum vitae -Prof. Dr. Awadallah Belal Dafaallah

Pre-emergence Application of Imazethapyr for Weed Control in Soybean (Glycine max (L.) Merr.), Gezira State, Sudan

International Journal of Academic Multidisciplinary Research, 2022

Soybean is one of the most important crops grown for the purpose of oil production in many countr... more Soybean is one of the most important crops grown for the purpose of oil production in many countries of the world. In the State of Sudan, in recent years, the interest in the soybean crop has increased due to the increase in demand and the lack of supply for the crop in the local market, as well as the importance of the crop in many industries, especially food. Weeds are one of the factors that negatively affect the production and productivity of the soybean crop. The current study was conducted with the aim of assessing the pre-emergence application of the chemical imazethapyr in weed management of soybeans in Gezira State, Sudan. A field experiment was conducted at the farm of Gezira Research Station of the Agricultural Research Corporation in Wad Medani, Sudan during the 2018/19 agricultural season. Three doses (0.0375, 0.050, and 0.0625 kg ai ha-1) of imazethapyr (Pursuit® 100 SL) were used as a pre-emergence treatment. For comparison, weeded and un-wedded treatments were used as a control. A randomized complete block designed was used and each treatment was replicated four times. Descriptive analysis and analysis of variance were performed to analyze data. Duncan's Multiple Range test was used for separation of the means. The results showed that all tested herbicide doses were effective in controlling weeds. The three doses significantly decreased weed infestation in comparison with unweeded control and significantly increased the yield and different growth attributes of soybean compared un-weeded control treatment. Using of imazethapyr at the dose 0.0625 kg a.i. ha-1 significantly reduced weeds (grasses and broad leaf) in the crop. It was also the best in terms of growth and productivity. The highest yield of seed (1383.3 kg ha-1) was obtained in the herbicide at the dose 0.0625 kg a.i. ha-1. The results of chemical analysis for the detection of pesticide residues in soybean seeds showed that there were no residues of the tested pesticide. The study concluded that the use of imazethapyr at a dose of 0.0625 kg a.i. ha-1 as preemergence treatment is effective and safe in weed management in soybean crop.

Effects of Ecological Approach on the Management of Cotton aphid, Aphis gossypii (Glov) in Selected Cotton Genotypes, Gezira State, Sudan

World Cotton Research Conference-7, 2022

Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. U... more Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insecticides were used to control cotton insect pests, but in Gezira scheme cotton produced for the first three decades (1911-1945) without chemical control. That might be due to the balanced nature. This research aims to reduce the cost of production and mitigating the environmental pollution through managing cotton aphid, Aphis gossypii (Glov) via ecological approach at Gezira State, Sudan.

Effects of Ecological Approach on the Management of Cotton Mealybug, Phenacoccus solenopsis (Tinsley), in Selected Cotton Genotypes, Gezira State, Sudan

World Cotton Research Conference-7, 2022

Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. U... more Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insecticides were used to control cotton insect pests, but in Gezira scheme cotton produced for the first three decades (1911-1945) without chemical control. That might be due to the balanced nature. This research aims to reduce the cost of production and mitigating the environmental pollution through managing cotton mealybug, Phenacoccus solenopsis (Tinsley) via ecological approach at Gezira State, Sudan.

Effects of some Cultural Practices on the Management of the African Bollworm, Helicoverpa armigera Hun, Gezira State, Sudan

World Cotton Research Conference-7 , 2022

Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insec... more Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insecticides were used to control cotton insect pests, but in Gezira scheme cotton produced for the first three decades (1911-1945) without chemical control. That might be due to the balanced nature. This research aims to reduce the cost of production and mitigating the environmental pollution through managing the African bollworm, Helicoverpa armigera Hun. via cultural practices at Gezira State, Sudan. Two experiments were conducted at the Experimental Farm of the Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan during season 2013/14 and 2014/15. In each season a factorial experiment was conducted with three cotton varieties, two sowing dates and two spaces. The varieties were Seni 1, Brazili (LL) and Hamid local variety. The sowing dates were third week of June and July, whereas the spaces were 25 and 50 cm intra row. Treatments were arranged in a completely randomized block design with three replicates. The insect pest was recorded either for their presence or their damage that inflicted on cotton plants. Data were transformed as needed and subjected to analysis of variance (ANOVA) procedure. In general, the results showed that there were significant (P ≤ 0.05) interaction effects between cultivar, sowing date and spacing on the number of eggs, larvae and on percentage of shedding of flowers and buds caused by African bollworm. Significantly, the lowest number of eggs (0 eggs per 100 plants) was recorded in Seni 1 cultivar lately sown with wide spacing, while the highest number of eggs (2.8 eggs per 100 plants) was recorded in Hamid cultivar early sown with narrow spacing. Significantly, the lowest number of larvae (0-0.8 larvae per 100 plants) was recorded in Seni 1 cultivar early sown with narrow spacing, while the highest number of larvae (4.5-6.3 larvae per 100 plants) was recorded in Hamid cultivar early sown. Significantly, the percentage of shedding of flowers and buds (1.2-9 %) was recorded in Seni 1 cultivar early sown with either narrow or wide spacing, while the highest percentage of shedding of flowers and buds (26-31.2%) was recorded in Hamid cultivar lately sown. The highest weight was achieved by Seni 1 cultivar followed by Brazili (LL) cultivar and then by Hamid cultivar. In conclusion, to achieve the lowest incidence and damage to cotton the Gezira State, Sudan Seni 1 cultivar could be early sown (third week of June) with either narrow spacing (25 cm a part between holes).

Allelopathic Effects of Sweet Basil (Ocimumbasilicum L.) on Seed Germination and Seedling Growth of some Poaceous Crops

International Journal of Environment, Agriculture and Biotechnology, 2017

Phytotoxic effects of aqueous extracts of apple of sodom (Calotropis procera W.T) on seed germination of Ischaemum afrum (J.F.Gmel.) dandy using probit analysis

Agricultural and Food Science Journal of Ghana, 2019

This study was carried out to investigate the phytotoxic effects of aqueous extracts of leaves, i... more This study was carried out to investigate the phytotoxic effects of aqueous extracts of leaves, inflorescences, stems and roots of apple of Sodom ( Calotropis procera W.T) on seed germination of Ischaemum afrum using probit analysis. Laboratory experiments were carried out at the Faculty of Agricultural Sciences, University of Gezira, Sudan in season 2014/15. Ten concentrations of the aqueous extract of each part of apple of Sodom were prepared by sequential dilution of the stock extract (50g/l) with sterilized-distilled water to give 2.11, 4.21, 6.34, 8.42, 10.53, 12.63, 14.13, 16.84, 18.94 and 21.05 g/l. A control with sterilized-distilled water was included for comparison. Treatments were arranged in completely randomized design with four replicates. The seeds were examined for inhibition (%) in germination at three days after initial germination. Data were subjected to probit analysis procedure (P 0.5).The results showed that the aqueous extracts of all tested parts of apple of Sodom suppressed seed germination of the I. afrum and there was direct positive relationship between concentration (g/l) and inhibition (%). The result also revealed that the leaves aqueous extract of apple of Sodom was more toxic (LD 50 = 6.3 g/l) to the seeds of I. afrum followed by aqueous extract of inflorescences (LD 50 = 7.2 g/l), stems (LD 50 = 11.4 g/l) and roots (LD 50 = 12.7 g/l). The results indicated that the aqueous extracts of apple of Sodom had toxic effect to the seeds of the I. afrum and could offer potential for the development of alternative herbicides. Keywords: Allelopathy; Apple of Sodom; Calotropis; Ischaemum; Phytotoxic; Probit

1 Design and Analysis of Agricultural Experiments

12 Duncan's multiple range test (DMRT)

DMRT is one of the most common methods used in comparing treatment means. This test is summarized... more

4 Steps Followed in Conducting Scientific Research

Before conducting exp. Design of exp. After conducting exp.

13 Design and Analysis of Factorial Experiments using Completely Randomized Design (CRD)

Factorial experiment is an experiment in which treatments are all possible combinations between s... more

2 Agricultural Experiments and their Importance

Introduction Experiment Agricultural Experiments Design and analysis of experiments Requirements ... more

10 Orthogonal polynomial contrast

The basic aim of the use of the orthogonal polynomial contrast is to study the response curve so ... more

3 Scientific Terms

9 Orthogonal contrast

16 Split Blocks Design or Strip Plots Design

This design is used in experiments involving the study of two different factors. The first factor... more This design is used in experiments involving the study of two different factors. The first factor (A) is usually called the vertical factor and the second factor (B) is the horizontal factor. This design is used in situations where vertical and horizontal interaction is more accurately measured than the main factors.

5 Principles of Experimental Designs and Analysis

Experimental error Basic principles of experimental designs Assumptions of analysis of virulence ... more

Association of Aquatic Weed Abundance and Water Quality, Gezira Scheme Canals, Sudan

Journal of Research in Weed Science, 2023

Water weeds are notorious for causing various troubles. Gezira Scheme in Sudan is being choked by... more Water weeds are notorious for causing various troubles. Gezira Scheme in Sudan is being choked by the increasing proliferation of aquatic weeds. This study aimed to look at the association between aquatic weed abundance and water quality in some canals in Sudan's Gezira Scheme in the year 2018. The study area included 18 sites, i.e. 6 canals classified into 3 parts (beginning, middle, and end). The abundance of aquatic weed species was evaluated visually at each site using a scale of (0-5), and water quality was examined by assessing physical, chemical, and biological properties. Descriptive statistics and variance analysis were used to analyze the data. The findings revealed that community structure was comprised of significant changes in the abundance of aquatic weed species throughout the year, as follows: floating (1.7-2.1), emergent (0.2-0.3), submergent (0.3), and bank aquatic weeds (1.5-2.2). In winter and summer, the most abundant species were Vossia cuspidata (4.0) and Cynodon dactylon (3.0-3.7). Temperature and turbidity were shown to be the most critical elements in restricting the development and abundance of aquatic weeds, along with alkalinity, salinity, and nutrients. The canals are habitat to a diverse range of living organisms, including animals, bacteria, fungi, and algae, which indicates the water's appropriateness for the presence and development of aquatic weeds. All of these insights will be valuable in the management of aquatic weeds in Gezira scheme's canals.

Efficacy and Selectivity of S-Metolachlor for Weed Control in Sugar Beet (Beta vulgarisL.), Gezira State, Sudan

Sudan University of Science and Technology, Dec 1, 2020

Curriculum vitae -Prof. Dr. Awadallah Belal Dafaallah

Curriculum vitae -Prof. Dr. Awadallah Belal Dafaallah

Pre-emergence Application of Imazethapyr for Weed Control in Soybean (Glycine max (L.) Merr.), Gezira State, Sudan

International Journal of Academic Multidisciplinary Research, 2022

Soybean is one of the most important crops grown for the purpose of oil production in many countr... more Soybean is one of the most important crops grown for the purpose of oil production in many countries of the world. In the State of Sudan, in recent years, the interest in the soybean crop has increased due to the increase in demand and the lack of supply for the crop in the local market, as well as the importance of the crop in many industries, especially food. Weeds are one of the factors that negatively affect the production and productivity of the soybean crop. The current study was conducted with the aim of assessing the pre-emergence application of the chemical imazethapyr in weed management of soybeans in Gezira State, Sudan. A field experiment was conducted at the farm of Gezira Research Station of the Agricultural Research Corporation in Wad Medani, Sudan during the 2018/19 agricultural season. Three doses (0.0375, 0.050, and 0.0625 kg ai ha-1) of imazethapyr (Pursuit® 100 SL) were used as a pre-emergence treatment. For comparison, weeded and un-wedded treatments were used as a control. A randomized complete block designed was used and each treatment was replicated four times. Descriptive analysis and analysis of variance were performed to analyze data. Duncan's Multiple Range test was used for separation of the means. The results showed that all tested herbicide doses were effective in controlling weeds. The three doses significantly decreased weed infestation in comparison with unweeded control and significantly increased the yield and different growth attributes of soybean compared un-weeded control treatment. Using of imazethapyr at the dose 0.0625 kg a.i. ha-1 significantly reduced weeds (grasses and broad leaf) in the crop. It was also the best in terms of growth and productivity. The highest yield of seed (1383.3 kg ha-1) was obtained in the herbicide at the dose 0.0625 kg a.i. ha-1. The results of chemical analysis for the detection of pesticide residues in soybean seeds showed that there were no residues of the tested pesticide. The study concluded that the use of imazethapyr at a dose of 0.0625 kg a.i. ha-1 as preemergence treatment is effective and safe in weed management in soybean crop.

Effects of Ecological Approach on the Management of Cotton aphid, Aphis gossypii (Glov) in Selected Cotton Genotypes, Gezira State, Sudan

World Cotton Research Conference-7, 2022

Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. U... more Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insecticides were used to control cotton insect pests, but in Gezira scheme cotton produced for the first three decades (1911-1945) without chemical control. That might be due to the balanced nature. This research aims to reduce the cost of production and mitigating the environmental pollution through managing cotton aphid, Aphis gossypii (Glov) via ecological approach at Gezira State, Sudan.

Effects of Ecological Approach on the Management of Cotton Mealybug, Phenacoccus solenopsis (Tinsley), in Selected Cotton Genotypes, Gezira State, Sudan

World Cotton Research Conference-7, 2022

Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. U... more Background: Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insecticides were used to control cotton insect pests, but in Gezira scheme cotton produced for the first three decades (1911-1945) without chemical control. That might be due to the balanced nature. This research aims to reduce the cost of production and mitigating the environmental pollution through managing cotton mealybug, Phenacoccus solenopsis (Tinsley) via ecological approach at Gezira State, Sudan.

Effects of some Cultural Practices on the Management of the African Bollworm, Helicoverpa armigera Hun, Gezira State, Sudan

World Cotton Research Conference-7 , 2022

Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insec... more Cotton is grown in Sudan as rainfed crop, as well as grown by permanent irrigation. Usually insecticides were used to control cotton insect pests, but in Gezira scheme cotton produced for the first three decades (1911-1945) without chemical control. That might be due to the balanced nature. This research aims to reduce the cost of production and mitigating the environmental pollution through managing the African bollworm, Helicoverpa armigera Hun. via cultural practices at Gezira State, Sudan. Two experiments were conducted at the Experimental Farm of the Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan during season 2013/14 and 2014/15. In each season a factorial experiment was conducted with three cotton varieties, two sowing dates and two spaces. The varieties were Seni 1, Brazili (LL) and Hamid local variety. The sowing dates were third week of June and July, whereas the spaces were 25 and 50 cm intra row. Treatments were arranged in a completely randomized block design with three replicates. The insect pest was recorded either for their presence or their damage that inflicted on cotton plants. Data were transformed as needed and subjected to analysis of variance (ANOVA) procedure. In general, the results showed that there were significant (P ≤ 0.05) interaction effects between cultivar, sowing date and spacing on the number of eggs, larvae and on percentage of shedding of flowers and buds caused by African bollworm. Significantly, the lowest number of eggs (0 eggs per 100 plants) was recorded in Seni 1 cultivar lately sown with wide spacing, while the highest number of eggs (2.8 eggs per 100 plants) was recorded in Hamid cultivar early sown with narrow spacing. Significantly, the lowest number of larvae (0-0.8 larvae per 100 plants) was recorded in Seni 1 cultivar early sown with narrow spacing, while the highest number of larvae (4.5-6.3 larvae per 100 plants) was recorded in Hamid cultivar early sown. Significantly, the percentage of shedding of flowers and buds (1.2-9 %) was recorded in Seni 1 cultivar early sown with either narrow or wide spacing, while the highest percentage of shedding of flowers and buds (26-31.2%) was recorded in Hamid cultivar lately sown. The highest weight was achieved by Seni 1 cultivar followed by Brazili (LL) cultivar and then by Hamid cultivar. In conclusion, to achieve the lowest incidence and damage to cotton the Gezira State, Sudan Seni 1 cultivar could be early sown (third week of June) with either narrow spacing (25 cm a part between holes).

Allelopathic Effects of Sweet Basil (Ocimumbasilicum L.) on Seed Germination and Seedling Growth of some Poaceous Crops

International Journal of Environment, Agriculture and Biotechnology, 2017

Phytotoxic effects of aqueous extracts of apple of sodom (Calotropis procera W.T) on seed germination of Ischaemum afrum (J.F.Gmel.) dandy using probit analysis

Agricultural and Food Science Journal of Ghana, 2019

This study was carried out to investigate the phytotoxic effects of aqueous extracts of leaves, i... more This study was carried out to investigate the phytotoxic effects of aqueous extracts of leaves, inflorescences, stems and roots of apple of Sodom ( Calotropis procera W.T) on seed germination of Ischaemum afrum using probit analysis. Laboratory experiments were carried out at the Faculty of Agricultural Sciences, University of Gezira, Sudan in season 2014/15. Ten concentrations of the aqueous extract of each part of apple of Sodom were prepared by sequential dilution of the stock extract (50g/l) with sterilized-distilled water to give 2.11, 4.21, 6.34, 8.42, 10.53, 12.63, 14.13, 16.84, 18.94 and 21.05 g/l. A control with sterilized-distilled water was included for comparison. Treatments were arranged in completely randomized design with four replicates. The seeds were examined for inhibition (%) in germination at three days after initial germination. Data were subjected to probit analysis procedure (P 0.5).The results showed that the aqueous extracts of all tested parts of apple of Sodom suppressed seed germination of the I. afrum and there was direct positive relationship between concentration (g/l) and inhibition (%). The result also revealed that the leaves aqueous extract of apple of Sodom was more toxic (LD 50 = 6.3 g/l) to the seeds of I. afrum followed by aqueous extract of inflorescences (LD 50 = 7.2 g/l), stems (LD 50 = 11.4 g/l) and roots (LD 50 = 12.7 g/l). The results indicated that the aqueous extracts of apple of Sodom had toxic effect to the seeds of the I. afrum and could offer potential for the development of alternative herbicides. Keywords: Allelopathy; Apple of Sodom; Calotropis; Ischaemum; Phytotoxic; Probit

1 Design and Analysis of Agricultural Experiments

12 Duncan's multiple range test (DMRT)

DMRT is one of the most common methods used in comparing treatment means. This test is summarized... more

4 Steps Followed in Conducting Scientific Research

Before conducting exp. Design of exp. After conducting exp.

13 Design and Analysis of Factorial Experiments using Completely Randomized Design (CRD)

Factorial experiment is an experiment in which treatments are all possible combinations between s... more

2 Agricultural Experiments and their Importance

Introduction Experiment Agricultural Experiments Design and analysis of experiments Requirements ... more

10 Orthogonal polynomial contrast

The basic aim of the use of the orthogonal polynomial contrast is to study the response curve so ... more

3 Scientific Terms

9 Orthogonal contrast

16 Split Blocks Design or Strip Plots Design

This design is used in experiments involving the study of two different factors. The first factor... more This design is used in experiments involving the study of two different factors. The first factor (A) is usually called the vertical factor and the second factor (B) is the horizontal factor. This design is used in situations where vertical and horizontal interaction is more accurately measured than the main factors.

5 Principles of Experimental Designs and Analysis

Experimental error Basic principles of experimental designs Assumptions of analysis of virulence ... more

14 Design and Analysis of Factorial Experiments using Randomized Complete Block Design (RCBD)

Factorial experiment is an experiment in which treatments are all possible combinations between s... more

13 Design and Analysis of Factorial Experiments using Completely Randomized Design (CRD)

Factorial experiment is an experiment in which treatments are all possible combinations between s... more

18 Covariance Analysis

Analysis of covariance is a technique that sometimes improves the accuracy of the experiment.

17 Combine Analysis of Variance

The performance of agricultural crops depends on the genetic composition, the environment in whic... more

16 Split Blocks Design or Strip Plots Design

This design is used in experiments involving the study of two different factors. The first factor... more This design is used in experiments involving the study of two different factors.
The first factor (A) is usually called the vertical factor and the second factor (B) is the horizontal factor.
This design is used in situations where vertical and horizontal interaction is more accurately measured than the main factors.

15 Split Plots Design

The split plots design is used in experiments involving the study of two different factors.

12 Duncan's multiple range test (DMRT)

DMRT is one of the most common methods used in comparing treatment means. This test is summarized... more

11 Least Significant Difference

LSD is considered by many researchers as the best method to compare multiple means for easy holdi... more LSD is considered by many researchers as the best method to compare multiple means for easy holding and then to the accuracy of the access to the correct results.
This test also called protected least significant difference, because the Fisher (author) does not recommend using the test unless the F-cal for treatments is significant.
LSD is original T-test which is used to compare differences between two means.

6 Completely Randomized Design (CRD)

Completely randomized design is the simplest, most easily understood, and most easily analyzed de... more

10 Orthogonal polynomial contrast

The basic aim of the use of the orthogonal polynomial contrast is to study the response curve so ... more

9 Orthogonal contrast

Orthogonal contrasts test also noun as orthogonal coefficients and Class comparisons. Orthogonal ... more Orthogonal contrasts test also noun as orthogonal coefficients and Class comparisons.
Orthogonal comparison test is used in experiments that have three or more treatments and the researcher wishes to implement specific comparisons prior experimentation and wants to be tested in the variance analysis.

8 Latin Square Design (LSD)

Latin square design is one of most experimental design used in agricultural research, particularl... more

7 Randomized Complete Block Design (RCBD)

Randomized complete block design is most used design in agricultural research, particularly in fi... more

5 Principles of Experimental Designs and Analysis

Experimental error Basic principles of experimental designs Assumptions of analysis of virulence ... more

4 Steps Followed in Conducting Scientific Research

Before conducting exp. Design of exp. After conducting exp.

3 Scientific Terms

Statistic Statistical population Sample Factor Treatment Control Interaction Experimental unit Sa... more

2 Agricultural Experiments and their Importance

Dr. Awadallah Belal Dafaallah, 2019

Introduction Experiment Agricultural Experiments Design and analysis of experiments Requireme... more

1 Design and Analysis of Agricultural Experiments: Objectives, Contents, Practical and References

Dr. Awadallah Belal Dafaallah, 2019

Objectives: Contents: Practical: References:

Host specificity of Sudan witchweed (Striga hermonthica [Del.] Benth.) seed germination and haustorium initiation in response to sorghum root exudates and extracts

Field surveys and laboratory experiments were conducted during the season 2009/10 and 2010/11 ... more Field surveys and laboratory experiments were conducted during the season 2009/10 and 2010/11 in witchweed (Striga hermonthica [Del.] Benth.) endemic areas in Sudan to investigate the host specificity of witchweed populations collected from different locations with respect seed germination and haustorium initiation in response to sorghum root exudates and extracts. Field surveys were conducted to collect seeds from witchweed plants growing under their respective hosts; sorghum and millet. A total of fifteen witchweed populations were collected. Tow in vitro experiments were conducted at the Phytopathology Center and Biology Laboratory, Faculty of Agricultural Sciences, University of Gezira, Sudan to study the effects of root exudates and root extracts of sorghum cv. Abu-70, cv. Wad Ahmed and cv. Hakika on percentage of seed germination and haustorium initiation. Treatments (fifteen witchweed populations and three sorghum cultivars) were arranged in a factorial completely randomized design with three replicates. Data were collected and subjected to analysis of variance. Means were separated for significant using Duncan's Multiple Range Test (at p  0.5). The results showed that, there were significant differences in seed germination and haustorium initiation of witchweed in response to root exudates and root extracts among sorghum cultivars and among the witchweed populations. However, the highest seed germination and haustorium initiation percentages attained by each of the witchweed population were on their respective hosts. This study suggests two levels of physiological specialization in witchweed in Sudan: intercrop specialization and intra-crop specialization. Moreover, two strains of witchweed are suggested, one specific to sorghum and the other, to millet. The existence of variability and host specificity within witchweed populations are suggested to be based almost entirely on differential response of Striga isolates to root exudates and root extracts from host.

Allelopathic effects of Jimsonweed (Datura stramonium L.) seed on seed germination and seedling growth of some leguminous crops

Laboratory and greenhouse experiments were carried out at the Faculty of Agricultural Sciences... more Laboratory and greenhouse experiments were carried out at the Faculty of Agricultural Sciences, University of Gezira, Sudan in season 2014/15. Laboratory experiments were conducted to study the allelopathic effect of aqueous extract of Jimsonweed (Datua stramonium L.) seed on seed germination of common bean (Phaseolus vulgaris L.), cowpea (Vigna sinensis [L.] Walp.), pigeon pea (Cajanus cajan [L.] Millsp.) and alfalfa (Medicago sativa L.). Six concentrations (0, 20, 40, 60, 80 and 100%) of the aqueous extract were prepared from the stock solution. Treatments, for each crop, were arranged in completely randomized design with four replicates. The seeds were examined for germination at three days after initial germination. Greenhouse experiments were conducted to study the allelopathic effect of Jimsonweed seed powder on seedling growth of the same crops. Seed powder was incorporated into the soil at rate of 0, 1, 2, 3, 4 and 5% on w/w biases in pots. Treatments, for each crop, were arranged in completely randomized design with four replicates. Experiments were terminated at 30 days after sowing and plant height, number of leaves and root length of crop seedlings were measured as well as plant fresh and dry weight. Data were collected and subjected to analysis of variance procedure. Means were separated for significance using Duncan`s Multiple Range Test at p  0.5. The results showed that the aqueous extract of Jimsonweed significantly reduced seed germination of the tested leguminous crops and there was direct negative relationship between concentration seed germination. Also, the results showed that incorporating seed powder into the soil significantly decreased plant height, root length of crop seedlings as well as seedling fresh and dry weight. In addition, the reduction in seedling growth was increased as seed powder increased in the soil. However, the number leaves did not affected. It concludes that Jimsonweed has allelopathic affects on seed germination and seedling growth of the leguminous crops.

The Efficacy of the Entomopathogenic Fungus, Metarhizium anisoppliae Sorokin (Sudanese Strain) on Puparia of Bactrocera dorsalis

The Watermelon (Citrullus lanatus) occupies second place in the world as a vegetables crop in ter... more The Watermelon (Citrullus lanatus) occupies second place in the world as a vegetables crop in terms of quantity of production. The watermelon bug, Coridius vidiatus is considered one of the most important watermelon insect pests in Sudan, especially in Kordofan and Darfour causes’ highly economic damage in the production areas of watermelon in rainfall sector. Biological control of arthropod pests has a long history of useful practical application. Parasites, predators, and pathogens have been efficiently employed in many cases to control arthropod pests. The objective of this study were to evaluate the efficacy of the fungus Metarhizium anisopliae with three different concentrations (0.2g, 0.3g, 0.4g/100 ml diesel and 0.2g, 0.3g, and 0.4g/100 ml water) applied by a 2-liter sprayer on the adult stage of the watermelon bug under laboratory conditions; using completely randomized design (CRD) with four replications and three treatments in addition to the control (water and diesel). The data was collected, by observing insect mortality every 12 hours for diesel preparations and every two days for water preparations. The results showed that the mortality rate increased with an increase in concentrations of the fungus. Diesel preparations recorded higher mortalities than aqueous preparations corrected for control mortality. The pathogenicity was high in the first two days with no significant differences between treatments, while in the third and fourth days, highly significant differences were found between treatments and control; the pathogenicity increased when the concentration was high. Also, the virulence increased with high concentration. Field trials would be necessary to put these results in perspectives of field use.

Effects of 2, 4-D and Nitrogen on Striga hermonthica (Del.) Benth. Incidence, Sorghum (Sorghum bicolor (L.) Moench) Growth and Parasitism

Variability and Host Specificity of Striga hermonthica (Del.) Benth. Populations in the Sudan

Striga spp., Orobanchaceae, are obligate root parasites on important cereals and leguminous crops... more Striga spp., Orobanchaceae, are obligate root parasites on important cereals and leguminous crops in Sub-Saharan Africa. Existence of physiological strains, ecological variants and races of the parasite together with variability in size of the seed bank offer serious obstacles for development of simple and effective control measures. Field surveys, laboratory and greenhouse experiments were conducted during seasons 2008/2009 and 2009/2010 to investigate variability and host specificity of Striga hermonthica (Del.) Benth. Field surveys were conducted during the rainy season in endemic areas in Eastern, Central and Western Sudan to investigate i) variability within S. hermonthica populations with respect to morphological characters, ii) possible reductions in growth and yield attributes of host and iii) relationship between the parasite and soil characteristics. Five locations were selected at random in each region. The laboratory and greenhouse experiments, designed to study host specificity and physiological variability, were undertaken at the Faculty of Agricultural Sciences, University of Gezira. S. hermonthica seeds used in these studies were collected from under sorghum in Eastern and Central Sudan, and millet in Western Sudan. Sorghum (cv. Abu-70) and millet (cv. Ashana) were used as test plants. In the laboratory studies, effects of GR 24, root exudates and root extracts of Abu-70 and Ashana on germination and early developmental stages were investigated. The green house experiments were setup to evaluate differential virulence of S. hermonthica populations on the aforementioned cereal cultivars. Treatments were laid in a randomized complete block design (RCBD) with three replications. Growth and harvest attributes on the parasite and crops were determined. Data were transformed, when necessary and subjected to statistical analysis as appropriate. The results of the surveys revealed that, S. hermonthica was pre-dominant on sorghum in Eastern and Central Sudan. While, in Western Sudan the parasite was reported on both sorghums and millet. S. hermonthica populations collected from Eastern Sudan showed the highest incidence, growth and harvest attributes followed, in descending order, by populations collected from western and central Sudan. S. hermonthica populations, invariably, showed considerable variations in flower characters. Striga infestation, on the average, reduced growth of sorghum and millet by 53.3 and 64.3%, and yield by 79.7 and 91.7%, respectively. The parasite effected significant differences in growth reduction and yield losses within cultivars, among locations and within locations. Striga population density, height, number of leaves, number of internodes and shoot dry weight were negatively (r = – 0.99 to – 0.7) correlated with pH, nitrogen, available phosphorous and exchangeable potassium in soils. However, they were positively (r = 0.89- 0.97) correlated with total carbon. The laboratory experiments revealed that, root exudates and extracts of all plants induced seed germination and haustorium initiation in S. hermonthica. The highest attachment and penetration attained by each of the were on their respective hosts. The greenhouse experiments showed that emergent S. hermonthica, capsules per plant, shoot dry weight and underground Striga plantlets were highest on the respective host. It is noteworthy that some of the Striga, sorghum populations, displayed limited emergence on millet and produced seeds. S. hermonthica populations significantly reduced growth and yield of sorghum and millet. However, the magnitude of the damage attained, by each population was highest on the respective host. These findings suggest the existence of both inter-and intra-crop specialization. Moreover, the results confirmed the existence of two strains of S. hermonthica, one specific to sorghum and the other to millet. These findings showed clearly the complexity of obtaining sorghum and millet cultivars with high and durable resistance across locations.

Fundamentals of Design and Analysis of Agricultural Experiments (Observation – Experimentation –Discussion), Part Two

University of Gezira , 2017

Dafaallah, A. B. (2017). Fundamentals of Design and Analysis of Agricultural Experiments (Observa... more

Fundamentals of Design and Analysis of Agricultural Experiments (Observation – Experimentation –Discussion), Part One

University of Gezira , 2017

Dafaallah, A. B. (2017). Fundamentals of Design and Analysis of Agricultural Experiments (Observa... more

Sustainable Management of Invasive Pests in Africa. Sustainability in Plant and Crop Protection

Springer, 2020

Sustainable Management of Invasive Pests in Africa. Sustainability in Plant and Crop Protection