Studies are being conducted which aim to improve the efficiency of irrigation and N fertilization for lemons produced on sandy soils in the low desert. The first experiment evaluates the response of 'Lisbon' lemons to various... more
Studies are being conducted which aim to improve the efficiency of irrigation and N fertilization for lemons produced on sandy soils in the low desert. The first experiment evaluates the response of 'Lisbon' lemons to various flood irrigation intervals. Irrigation intervals are based on soil moisture depletion (SMD) as calculated from frequent neutron probe soil moisture measurements. Individual treatments were irrigated when total SMD was 25 %, 40 %, 55 %, and 70 %, respectively. The second experiment compares the performance of young lemons produced under flood, trickle, and micro -spray irrigation systems. The third experiment evaluates the response of young lemons to water and N combinations (3 by 3 factorial) under micro -spray irrigation. The three irrigation rates were targeted for 30 cnbar, 20 cnbar, and 10 cnbar tension. The three N rates were 0.1, 0.2, and 0.4 kg N /tree. One flood irrigation treatment was added for comparative purposes. Overall, results obtained i...
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This experiment was established in January 2000 in a block of 'Washington'navel orange trees at Verde Growers, Stanfield, AZ. Treatments included: normal grower practice, winter low biuret (LB) urea application, summer LB urea... more
This experiment was established in January 2000 in a block of 'Washington'navel orange trees at Verde Growers, Stanfield, AZ. Treatments included: normal grower practice, winter low biuret (LB) urea application, summer LB urea application, winter LB urea application ...
Lisbon lemons were treated with N levels ranging from 0.5 to 3.0 lbs. N per tree annually. Fourth–season yield results from the trial show significant effects of the treatments upon overall yield and leaf N concentrations, but no effect... more
Lisbon lemons were treated with N levels ranging from 0.5 to 3.0 lbs. N per tree annually. Fourth–season yield results from the trial show significant effects of the treatments upon overall yield and leaf N concentrations, but no effect upon fruit packout. Treatments did lead to a significant effect upon leaf nutrient concentration. Total cumulative yields from 2008 to 2012 (not including the freeze-affected 2011-12 season) were significantly affected by the treatments. Trees treated annually with 2.0 lbs N had the greatest yield, which represented a 12% increase over the yield of trees treated with just 0.5 lbs. N annually.
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Five rootstocks, ‘Carrizo’ citrange, Citrus macrophylla, Rough lemon, Swingle citrumelo and Citrus volkameriana were selected for evaluation using 'Limoneira 8A Lisbon' as the scion. 1999-2000 results indicate that trees on C.... more
Five rootstocks, ‘Carrizo’ citrange, Citrus macrophylla, Rough lemon, Swingle citrumelo and Citrus volkameriana were selected for evaluation using 'Limoneira 8A Lisbon' as the scion. 1999-2000 results indicate that trees on C. macrophylla and C. volkameriana are superior to those on other rootstocks in both growth and yield. C. macrophylla is outperforming C. volkameriana. Rough lemon is intermediate, and ‘Swingle’ and Carrizo’ are performing poorly. In a similar trial, Four 'Lisbon' lemon selections, 'Frost Nucellar', 'Corona Foothills', 'Limoneira 8A' and 'Prior' were selected for evaluation on Citrus volkameriana rootstock. 1998-99 results indicate that the 'Limoneira 8A Lisbon' and ‘Corona Foothills Lisbon’ are superior in yield and fruit earliness. Results from another lemon cultivar trial suggest that ‘Cavers Lisbon’, Limonero Fino 49’ and “Villafranca’ lemons may be good candidates for plantings as well. Results from two...
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The aim of this study was the evaluation of date palm (Phoenix dactylifera L.) pollen production during the 2021 and 2022 seasons in the Mexicali Valley, Mexico. Twelve seed-propagated male palms of 20 years of age and similar vigor were... more
The aim of this study was the evaluation of date palm (Phoenix dactylifera L.) pollen production during the 2021 and 2022 seasons in the Mexicali Valley, Mexico. Twelve seed-propagated male palms of 20 years of age and similar vigor were selected and grouped into four groups with phenotypic characteristics of the common female cultivars in the area (Medjool, Deglet Noor, Khadrawy, and Zahidi). The pollen was extracted manually, with average production among all individuals of 780.94 and 777.11 g, in 26 and 24 inflorescences, respectively, for each year. Likewise, the flowering period on average was 47 and 41 days for each year. The pollen extracted from the earliest four inflorescences averaged 38.7 and 32.55 g, while that of the latest one produced 10.70 g and 18.28 g for each year, respectively. Seedling male palms with a phenotype similar to the Deglet Noor cultivar produced the greatest amount of pollen with 1250.98 and 1114.26 g on average for each year, produced during a late,...
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The date palm (Phoenix dactylifera L.) originated in the Arabian Peninsula, spread throughout North Africa, then was carried to Mexico and the United States. Planting began in earnest in Arizona and California in the late 1800s and... more
The date palm (Phoenix dactylifera L.) originated in the Arabian Peninsula, spread throughout North Africa, then was carried to Mexico and the United States. Planting began in earnest in Arizona and California in the late 1800s and continues today. As of 2014, date production in Mexico and the United States is valued at almost $13,000,000, and comprises about 7400 ha. ‘Deglet Noor’ and ‘Medjool’ are the major cultivars. Modern practices for date palm cultivation include planting, irrigation, fertilization, pollination, thinning the fruit, ringing the bunches, bagging the bunches, and harvest. After harvest, the fruit must be sorted, dried or rehydrated, and graded. Date palms are sometimes sold for landscaping purposes. Current research at the University of Arizona and University of California at Riverside is focused on pollination and thinning practices, improving fruit quality and controlling insects. There are four date palm germplasm collections located in Arizona and California.
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Blueberry reducers in Texas must often irrigate with sodic water. Excess Na+ leads to reduced growth, necrosis, and plant mortality. Ca2+ is known to ameliorate such detrimental effects in many crops, but little is known about the... more
Blueberry reducers in Texas must often irrigate with sodic water. Excess Na+ leads to reduced growth, necrosis, and plant mortality. Ca2+ is known to ameliorate such detrimental effects in many crops, but little is known about the response of rabbiteye blueberry. To elucidate the influence of Ca2+ on the uptake and translocation of Na+, plants were subjected to NaCl in hydroponics solutions (10, 25, 50 and 100 mM NaCl) and the uptake of Na+ was traced over a 24h period using 22Na+ Additionally, for each treatment, half the plants were supplied with 10 mM Ca2+. Plants were then transferred to identical, but unlabeled, solution, then harvested at intervals up to 28 days following cessation of labelling.Preliminary results indicate that plants subjected to 25 mM Na+ and 0 mM Ca2+ showed less ability to exclude Na+ from the roots, and accumulated more Na+ in roots, stems, an leaves than did plants supplied with 25 mM Na+ and 10 mM Ca2+. Leaf tissue accumulated more Na per gram fresh wei...
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Four orchard floor management strategies—disking, mowing, chemical mow, and clean culture using herbicides—were evaluated in a `Limoneira 8A Lisbon' lemon orchard in Southern Arizona, starting in the fall of 1993. Disking was the... more
Four orchard floor management strategies—disking, mowing, chemical mow, and clean culture using herbicides—were evaluated in a `Limoneira 8A Lisbon' lemon orchard in Southern Arizona, starting in the fall of 1993. Disking was the cultural practice used to manage the orchard floor before the start of the experiment. Although disking the orchard floor may have injured shallow tree roots, it provided satisfactory weed control except underneath the tree canopies where bermudagrass, purple nutsedge, and other weed species survived. Chemical mowing with Roundup at 1.168 L/ha did not provide satisfactory control of many weed species and required too many applications to be commercially feasible. This treatment was converted to a combination clean culture and disk treatment (clean and disk) in Summer 1995. Mowing the orchard suppressed broadleaf weed species, allowing the spread and establishment of grasses, primarily bermudagrass, and to a lesser extent, southern sandburr. A fall appli...
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We injected AGRA PHOS (Potassium Phosphite) 0-2.4-2, Propiconazole – 0.05%, Zn, Mn and Fe 0.105, 0.112, and 0.10% respectively, Zn, Mn and Fe 0.210, 0.220, and 0.200% respectively and Propiconazole – 0.05% + Zn, Mn and Fe 0.105, 0.112,... more
We injected AGRA PHOS (Potassium Phosphite) 0-2.4-2, Propiconazole – 0.05%, Zn, Mn and Fe 0.105, 0.112, and 0.10% respectively, Zn, Mn and Fe 0.210, 0.220, and 0.200% respectively and Propiconazole – 0.05% + Zn, Mn and Fe 0.105, 0.112, and 0.10% respectively using a low pressure injection system for the control of Antrodia sinuosa in lemon trees. No treatment led to a significant reduction in fungal growth.
Three orange cultivar trials have been established in Arizona, one at the Yuma Mesa Agricultural Center, Yuma, AZ and one at the Citrus Agriculture Center, Waddell, AZ. For the navel orange trial in Yuma, ‘Fisher’ navel continues to have... more
Three orange cultivar trials have been established in Arizona, one at the Yuma Mesa Agricultural Center, Yuma, AZ and one at the Citrus Agriculture Center, Waddell, AZ. For the navel orange trial in Yuma, ‘Fisher’ navel continues to have the greatest yield, but is unacceptably granulated For the Waddell trial, the second year data has been collected, and suggests that ‘Fisher’ and ‘BeckEarli’ are outperforming the other cultivars tested to date.
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We injected AGRA PHOS (Potassium Phosphite) 0-2.4-2, Propaconizole – 0.05%, Zn, Mn and Fe 0.105, 0.112, and 0.10% respectively, Zn, Mn and Fe 0.210, 0.220, and 0.200% respectively and Propaconizole – 0.05% + Zn, Mn and Fe 0.105, 0.112,... more
We injected AGRA PHOS (Potassium Phosphite) 0-2.4-2, Propaconizole – 0.05%, Zn, Mn and Fe 0.105, 0.112, and 0.10% respectively, Zn, Mn and Fe 0.210, 0.220, and 0.200% respectively and Propaconizole – 0.05% + Zn, Mn and Fe 0.105, 0.112, and 0.10% respectively using a low pressure injection system for the control of Antrodia sinuosa in lemon trees. No treatment led to a significant reduction in fungal growth.
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Four 'Lisbon' lemon selections, 'Frost Nucellar', 'Corona Foothills', 'Limoneira 8A' and 'Prior' were selected for evaluation on Citrus volkameriana rootstock. 2004-05 results indicate that the... more
Four 'Lisbon' lemon selections, 'Frost Nucellar', 'Corona Foothills', 'Limoneira 8A' and 'Prior' were selected for evaluation on Citrus volkameriana rootstock. 2004-05 results indicate that the 'Limoneira 8A Lisbon' and ‘Corona Foothills Lisbon’
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The effect of Roundup on lemon trees (Citrus limon) was evaluated by repeatedly spraying 0.5, 0.75, 1, 1.25, and 1.5 lb. a.i./acre (corresponding to 0.5, 0.75, 1, 1.25, 1.5 quarts of Roundup Ultra/acre) on the bottom 20 to 24 inches of... more
The effect of Roundup on lemon trees (Citrus limon) was evaluated by repeatedly spraying 0.5, 0.75, 1, 1.25, and 1.5 lb. a.i./acre (corresponding to 0.5, 0.75, 1, 1.25, 1.5 quarts of Roundup Ultra/acre) on the bottom 20 to 24 inches of the tree canopies, over a three year period. The Roundup applications caused significant leaf injury in the sprayed area of the canopies and there was also significant defoliation of branches at the higher Roundup rates in all three years of the study. In 1996 after three Roundup applications, increasing rates of Roundup had no effect on flower or fruitlet production in either the sprayed or unsprayed portions of the tree canopies as judged by the counts collected from branches in each canopy zone. Similarly, in 1997 after five Roundup applications, and in 1998 after nine Roundup applications, increasing rates of Roundup had no effect on flower or fruitlet production in the sprayed or unsprayed portions of the tree canopies. Spraying Roundup on the bo...
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Two lemon selection trials have been established in Yuma, AZ to determine whether any of the selections under test can surpass ‘Limoneira 8A Lisbon’ in yield, fruit size or exterior or interior fruit quality. In the 1997 trial, ‘Limonero... more
Two lemon selection trials have been established in Yuma, AZ to determine whether any of the selections under test can surpass ‘Limoneira 8A Lisbon’ in yield, fruit size or exterior or interior fruit quality. In the 1997 trial, ‘Limonero Fino 49’ had statistically equivalent yield and larger fruit size than ‘Limoneira 8A’. ‘Primofiori’, ‘Femminello Comune’, ‘Cavers Lisbon’ and ‘Cascade Eureka’ may also be suitable, but none consistently equal or surpass ‘Limoneira 8A Lisbon’ lemon in terms of overall yield and/or earliness as often as does ‘Limonero Fino 49’. In the 1998 trial, ‘Dr. Strong’ Lisbon often has greater yield than does ‘Limoneira 8A Lisbon’.
Research Interests: Engineering and Geography
Berry plants should be well-watered when set out. If plants are irrigated with a hose or a bubbler head, water every three to seven days for the first two months, depending on temperature. When established, they can be watered in this way... more
Berry plants should be well-watered when set out. If plants are irrigated with a hose or a bubbler head, water every three to seven days for the first two months, depending on temperature. When established, they can be watered in this way every one to two weeks. If drip or mini-sprinkler irrigation is used, apply one to two inches of water per week, irrigating every day when the plants are young, and every one to two days once the plants are established. Irrigate more frequently during dry, hot weather, when plants are flowering and when fruit is ripening.
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In a rootstock evaluation trial planted in 1993, five rootstocks, ‘Carrizo’ citrange, Citrus macrophylla, ‘Rough Lemon’, Swingle citrumelo and Citrus volkameriana were selected for evaluation using 'Limoneira 8A Lisbon' as the... more
In a rootstock evaluation trial planted in 1993, five rootstocks, ‘Carrizo’ citrange, Citrus macrophylla, ‘Rough Lemon’, Swingle citrumelo and Citrus volkameriana were selected for evaluation using 'Limoneira 8A Lisbon' as the scion. 1994-2006 yield and packout results indicate that trees on C. macrophylla, C. volkameriana and ‘Rough Lemon’ are superior to those on other rootstocks in both growth and yield. C. macrophylla does not consistently outperform C. volkameriana. ‘Swingle’ and Carrizo’ are performing poorly.
Introduction W. Murcott Afourer mandarin has been one of the most planted mandarins in California. It appears to have good fruit quality, does not granulate, is easy to peel, and has good yields. Most importantly, for the consumer, it can... more
Introduction W. Murcott Afourer mandarin has been one of the most planted mandarins in California. It appears to have good fruit quality, does not granulate, is easy to peel, and has good yields. Most importantly, for the consumer, it can be seedless. Seedlessness in mandarins requires that the fruit not be cross-pollinated. One of the primary ways to ensure that there will be no cross-pollination is by planting this variety in isolated areas, away from other citrus varieties. When there is an abundance of possible locations, such as in California, this is not difficult. However, in Arizona, where land is scarce, it is not always easy to isolate one citrus from others.
Realizing that the Arizona citrus industry might someday have to deal with widespread ACP control, the Arizona Citrus Research Council approved a trip to Florida and Texas to investigate how ACP control was accomplished in those two... more
Realizing that the Arizona citrus industry might someday have to deal with widespread ACP control, the Arizona Citrus Research Council approved a trip to Florida and Texas to investigate how ACP control was accomplished in those two states. The trips were to McAllen, Texas on 9-12 Nov 2011 and to Immokalee Florida on 17-18 Nov. 2011. In McAllen, I interviewed Dr. Mamoudou Setamou, extension entomologist for Texas A&M – Kingsville and his staff, and Mr. Ray Prewitt, president of Texas Citrus Mutual. In Florida, I interviewed Mr. Ron Hamel, manager of the Gulf Citrus Growers, and Dr. Mongi Zekri, southwest Florida Multi-County Citrus Agent, housed at the Hendry County Extension Office in LaBelle., FL. The author hopes that some of this information can be used in the development of an Area Wide Spray Plan in Arizona.
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Citrus trees are most likely to survive cold temperatures if they are planted in the proper location. The USDA has divided the US into eleven plant hardiness zones based on 10°F average annual minimum temperature1 ranges. Zones 2 through... more
Citrus trees are most likely to survive cold temperatures if they are planted in the proper location. The USDA has divided the US into eleven plant hardiness zones based on 10°F average annual minimum temperature1 ranges. Zones 2 through 10 are further subdivided (a and b) which represent 5° F differences within each 10° F zone. In Arizona, citrus may be safely grown in zone 10a, where average annual minimum temperatures range from 30 to 35oF, and in zone 9b, where average annual minimum temperatures range from 25 to 30oF. In zone 9a (20 to 25° F), citrus may be grown in areas with proper cold air drainage. These areas include the slopes surrounding Tucson, and some areas of Pinal County. Bottomland areas within zone 9a would not be acceptable, as cold air will accumulate. Citrus planted in the Rillito Creek and Gila River valleys of zone 9a, are highly susceptible to frost damage.
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The objective of this research was to determine the shelf life of ‘Valencia’ sweet oranges (Citrus sinensis (L.) Osbeck) stored in sealed polystyrene containers, within a refrigerated chamber with temperature 3 to 9 °C, high relative... more
The objective of this research was to determine the shelf life of ‘Valencia’ sweet oranges (Citrus sinensis (L.) Osbeck) stored in sealed polystyrene containers, within a refrigerated chamber with temperature 3 to 9 °C, high relative humidity (85%) and frequent air exchange by chamber compressor. Oranges were harvested directly from the orchard and washed with water with 150 mg L -1 sodium hypochlorite. We measured the color of the flavedo (peel) and the endocarp (pulp), polar and equatorial diameter, firmness of the pulp and total soluble solids concentration (°Brix) in the endocarp. The tone and purity of the yellow color of the flavedo and endocarp of the oranges increased significantly within the polystyrene containers. Within the containers, fruit quality was preserved and shelf life was extended for more than 100 days without symptoms of deterioration, reduction of polar and equatorial diameter or decrease in total soluble solids. Inside the polystyrene closed containers, the ...
Author(s): Wright, Glenn C.; Caravetta, G. John | Abstract: In October, 2009, about three months after the first find of Asian Citrus Psyllid (ACP) in San Luis Rio Colorado Sonora, a colony of ACP was found just across the border in San... more
Author(s): Wright, Glenn C.; Caravetta, G. John | Abstract: In October, 2009, about three months after the first find of Asian Citrus Psyllid (ACP) in San Luis Rio Colorado Sonora, a colony of ACP was found just across the border in San Luis Arizona. Since then, twelve additional sites have been found in Arizona, all except two in Yuma County. Less than 50 individual ACP have been found since 2009 and all have been eradicated. No ACP found in Arizona has yet tested positive for HLB. As of now, much of southwest Arizona is under federal quarantine for ACP and trees and fruit that move out of the quarantine area require special treatment. The response of the Arizona Department of Agriculture to the discovery of ACP has been to increase trapping and eradication activities using funds received from the Federal and State Government. The University of Arizona and the citrus industry have responded by establishing screenhouses to produce trees that can provide disease-free budwood. The ind...
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Citrus budding is a plant propagation technique that any homeowner can do. While it does require some skill, with a moderate amount of practice a homeowner can become proficient. Once the technique is learned, homeowners can add citrus... more
Citrus budding is a plant propagation technique that any homeowner can do. While it does require some skill, with a moderate amount of practice a homeowner can become proficient. Once the technique is learned, homeowners can add citrus varieties of their choice to their present citrus trees. The use of budding will lead to a producing tree sooner than if a seed were planted. Also a budded tree or branch will be genetically identical to its parent.
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Nut count (NC), trunk circumference (TC), competition factor (CF), days from budbreak (DAY), and high or low crop year (YR) data were collected on 40 trees at three sites across Texas in 1985 and 1986, to create a model that would predict... more
Nut count (NC), trunk circumference (TC), competition factor (CF), days from budbreak (DAY), and high or low crop year (YR) data were collected on 40 trees at three sites across Texas in 1985 and 1986, to create a model that would predict pecan [Carya illinoensis (Wangenh.) C. Koch] yield. The model developed predicted the natural logarithm of the total nuts on the tree [In(NUTS)]: In(NUTS) = 2.112 + [0.634 × In(NC)] + (0.00119 × TC) – (0.0701 × In(CF)) + (0.00639 × DAY) + (0.728 × YR). The equation accounts for 87% of the variation in yield. The model is not sufficiently accurate to predict individual tree yields well, but additional data show an ability to accurately predict average tree yields.
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Several orchard floor management strategies were evaluated beginning in Fall 1993 in a `Limoneira 8A Lisbon' lemon (Citrus limon) grove on the Yuma Mesa in Yuma, Ariz. and in a `Valencia' orange (Citrus sinensis) grove at the... more
Several orchard floor management strategies were evaluated beginning in Fall 1993 in a `Limoneira 8A Lisbon' lemon (Citrus limon) grove on the Yuma Mesa in Yuma, Ariz. and in a `Valencia' orange (Citrus sinensis) grove at the University of Arizona Citrus Agricultural Center, Waddell, Ariz. At Yuma, disking provided acceptable weed control except underneath the tree canopies where bermudagrass (Cynodon dactylon), purple nutsedge (Cyperus rotundus), and other weed species survived. Mowing the orchard floor suppressed broadleaf weed species allowing the spread of grasses, primarily bermudagrass. Preemergence (norflurazon and oryzalin) and postemergence (glyphosate and sethoxydim) herbicides were used to control weeds in the clean culture treatment in Yuma. After three harvest seasons (1994-95 through 1996-97), the cumulative yield of the clean culture treatment was 385 kg (848.8 lb) per tree, which was significantly greater than the 332 kg (731.9 lb) and 320 kg (705.5 lb) per t...
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A field trial conducted at Yuma, Ariz., examined the effect of foliar boron application on fruit yield and quality of Citrus sinensis cv. Hamlin. Boron was applied to 5-year-old trees at five treatment levels (0, 500, 1000, 2000, and 3000... more
A field trial conducted at Yuma, Ariz., examined the effect of foliar boron application on fruit yield and quality of Citrus sinensis cv. Hamlin. Boron was applied to 5-year-old trees at five treatment levels (0, 500, 1000, 2000, and 3000 ppm) before or after flowering in a split plot design. At harvest, fruit number, size and quality were determined. Yield (P = 0.01) and average fruit number per tree (P = 0.02) were different among treatments. The highest yield was obtained with the 500 ppm treatment. In this first year of the trial there was no difference in average fruit weight, fruit pH, titratable acidity, peel thickness, juice volume, or soluble solid content of fruit between the treatments. Previous studies indicate that boron influenced in vivo and in vitro pollen germination in many crops. Increased fruit yield may have occurred because boron was transported to the flowers where it exerted its influence on increased fruit set through an effect on pollen viability or pollen ...
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Growth of young lemon trees (Citrus limon Burm. f.) is extremely vigorous, and is characterized by the appearance of highly vigorous upright shoots that originate in the scaffold branches and trunk of the tree. While maturing, these... more
Growth of young lemon trees (Citrus limon Burm. f.) is extremely vigorous, and is characterized by the appearance of highly vigorous upright shoots that originate in the scaffold branches and trunk of the tree. While maturing, these shoots are considered to be in competition for photosynthates with smaller fruit in the spring and with mature fruit in the fall. During 1993 and 1994, we selectively removed these shoots 12, 6, 4, and 1 (1994 only) times per year, with the objective of increasing fruit size. Neither yield nor fruit quality was affected by the pruning treatments during 1993, but pruning trees 12 times per year increased fruit size by 30% compared to unpruned trees. In 1994, lemon trees pruned 4 times per year had 50% less cull fruit than unpruned trees, and 22% more fruit of size 140 or larger. However, >99% of the flowers and small fruit on trees pruned 4 times per year were aborted, compared with 95% abortion on the unpruned trees. Trees pruned 4 times per year also...
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Five rootstocks, `Carrizo' citrange, Citrus macrophylla, Rough lemon, `Swingle' citrumelo, and Citrus volkameriana, were selected for evaluation using `Limoneira 8A Lisbon' as the scion. Four years of yield and fruit packout... more
Five rootstocks, `Carrizo' citrange, Citrus macrophylla, Rough lemon, `Swingle' citrumelo, and Citrus volkameriana, were selected for evaluation using `Limoneira 8A Lisbon' as the scion. Four years of yield and fruit packout data indicate that trees on C. volkameriana and C. macrophylla are superior to those on other rootstocks in growth and yield. `Swingle' and `Carrizo' are performing poorly, and Rough lemon is intermediate. In a similar trial, four `Lisbon' lemon selections, `Frost Nucellar', `Corona Foothills', `Limoneira 8A', and `Prior' selections of Lisbon lemon were selected for evaluation on Citrus volkameriana rootstock. Four years of yield and packout data indicate that the `Limoneira 8A Lisbon' selection has generally outperformed the other selections in both growth and yield, although `Corona Foothills' has been superior in the 1998-99 harvest season.
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Arizona lemon producers are often concerned with poor flowering, fruit set and fruit sizing, especially following excessively warm winter or spring weather. `Limoneira 8A Lisbon' (Citrus limon Burm.) lemons were girdled over a 3-year... more
Arizona lemon producers are often concerned with poor flowering, fruit set and fruit sizing, especially following excessively warm winter or spring weather. `Limoneira 8A Lisbon' (Citrus limon Burm.) lemons were girdled over a 3-year period to determine if girdling would improve yield or fruit size. Eight trees were girdled each month, from November through August, using a double spiral girdle and a 4.8-mm wide girdling knife. Fruit size measurements were taken throughout the growing season. Trees were harvested individually, and yield; fruit packout and fruit quality measurements were collected. For the 1995/96 harvest, trees girdled in March and May had greater early size and greater yields. Fruit quality was improved as well. For 1996/97 harvest year, trees girdled the previous November and December had significantly greater yield and fruit size. For trees harvested in 1997/98, no treatment was significantly better than the non-girdled trees. The effects of girdling on the or...
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Two lemon [Citrus limon (L.) Burm.] cultivar selection trials are being conducted at the Yuma Mesa Agriculture Center in Somerton, Ariz. Some selections in these trials include: `Allen Eureka', `Berna', `Cook Eureka', `Cascade... more
Two lemon [Citrus limon (L.) Burm.] cultivar selection trials are being conducted at the Yuma Mesa Agriculture Center in Somerton, Ariz. Some selections in these trials include: `Allen Eureka', `Berna', `Cook Eureka', `Cascade Eureka', `Cavers Lisbon', `Strong Lisbon', `Femminello Comune', `Lapithkiotiki', `Limoneira 8A Lisbon', `Limonero Fino…
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Arizona Farm Safety Day has been held annually since 2000 as an attempt to educate students and farm workers (pesticide applicators, tractor and equipment operators, irrigators, and field workers) in farm safety. Our programs have... more
Arizona Farm Safety Day has been held annually since 2000 as an attempt to educate students and farm workers (pesticide applicators, tractor and equipment operators, irrigators, and field workers) in farm safety. Our programs have emphasized tractor safety, pesticide safety, ATV safety, electrical safety, and firearms safety. The all-day events have been held in Yuma and in Safford, Ariz., and most of the attendees are high school students. Agriculture students from six to eight high schools typically participate. The agenda is determined by consulting with local agriculture leaders. Attendees have the opportunity to attend a 4-hour training session in the morning. Subjects taught at these sessions might include reading a pesticide label, sprayer calibration, wearing proper protection, avoiding spray drift, tractor safety, and farm safety. At least one of these sessions is an outdoors “hands-on” session. Individual participants receive up-to-date information and literature, a certif...
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... Some trees can produce 100 kg of fruit (Paulsen, 2005) Once harvested, 'Medjool' dates are dried to 24 to 28% moisture content, rather than dried on the tree as are the 'Deglet Noor' dates. ...... more
... Some trees can produce 100 kg of fruit (Paulsen, 2005) Once harvested, 'Medjool' dates are dried to 24 to 28% moisture content, rather than dried on the tree as are the 'Deglet Noor' dates. ... Paulsen, ME 2005. The amazing story of the fabulous 'Medjool' date. ...