Boll Rot Research Articles

New germplasm from crossing Upland cotton (Gossypium hirsutum) with G. tomentosum

The data from this study indicate that cytoplasm may have some direct or indirect effects on inheritance and expression of measurable characteristics like petal color, fiber characteristics, and boll rot in cotton. This suggests that cytoplasmic diversity might supply an additional tool for taking advantage of the wide range of new genetic material that interspecific crosses could make available to breeders working with Upland cotton.

Dispersal of Airborne Spores of Boll-Rotting Fungi and the Incidence of Cotton Boll Rot

Dispersal of Airborne Spores of Boll-Rotting Fungi and the Incidence of Cotton Boll Rot

Factors affecting aflatoxin contamination of cottonseed I. Contamination of cottonseed withAspergillus flavus at harvest and during storage

Abstract and SummaryExamination of cottonseed production has shown that boll weevils (Anthonomus grandis), boll rots, and improper handling and storage conditions are critical factors inAspergillus flavus contamination of cotton‐seed.A. flavus cultures were isolated from both field‐collected and laboratory emerged boll weevils, as well as from boll weevil emergence holes. Diseased cotton bolls have been found to containA. flavus conidia. Infection byA. flavus was limited to the surface of cottonseeds collected from gin and from the gin blower. Seeds improperty stored outside the gin were infected internally withA. flavus. Observation of bright greenish‐yellow fluorescence was not useful as a diagnostic procedure to detect contaminated seeds. Aflatoxin‐producing potential ofA. flavus isolates is being investigated. WhenA. flavus conidia were artifically inoculated onto the surface of the seeds, 87% of the seeds from Athens, GA, were internally infected whereas only 29% of the seeds from Macon, GA, were internally infected.A. flavus invade the cottonseed embryo through the chalazal region, the micropylar region, or cracks developed in the seed coat during ginning. Invasion of cottonseed byA. flavus was predominant at 28, 30, and 37 C while at 15 and 20 C other fungi dominated in surface and internal invasions of cottonseed. At relative humidities of 75% and 80%,Chaetomium spp. successfully competed in growth on the surface, while at a relative humidity of 90% and above, fungi belonging to the orderMucorales outgrewA. flavus.

Botryodiplodia theobromae . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Botryodiplodia theobromae . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Plurivorous, on approximately 500 host plants (30, 181; Wellman, 1954; Goss et al. , 1961). Also isolated from ulcerated human cornea, lesions on nail and subcutaneous tissue. DISEASES: Causing or associated with damping-off, wilt, blight, die-back, root rot, collar rot, stem necrosis, panel necrosis of rubber, gummosis, black band disease of jute, stump rot, bole rot, rot of sugarcane, leaf spot, witches' broom, fruit blight, fruit rot, pod rot of cacao, boll rot of cotton, seed rot, storage rot of cassava, sweet potato and yams. Also causes loss of cuttings in cacao and budding failure in rubber. Blue staining of timber and blue spotting of crepe rubber. GEOGRAPHICAL DISTRIBUTION: World-wide but mainly confined to an area 40° north to 40° south of the equator. TRANSMISSION: By wind and water from decaying plantations and orchards (Meredith, 1961; Stover, 1972). Seed-borne in cacao, cotton, groundnut, loquat, Musa spp., rubber and Strophanthus intermedius (Noble & Richardson, 1968). Also by soil-borne conidia. It may be disseminated by insects (48, 2007; 51, 2936). Conidia on seeds viable for 4 months and mycelium for 1 yr. (44, 1223).

Effect of Leaf Shape on Response of Cotton to Plant Population, N Rate, and Irrigation1

AbstractLeaves varying in shape have been identified in cotton, and it has been conjectured that leaf shape affects growth and other quantitative characters in Upland cotton, Gossypium hirsutum L.The objective of these studies was to evaluate okra and normal leaf shape on boll rot, yield, earliness, boll size, and fiber properties. Near isogenic lines of okra and normal leaf shape cotton was evaluated at three plant populations (21,780, 32,670, and 65,338 plants/ha) and three N rates (100, 134, and 168 kg/ha) on an Appling coarse sandy loam (Typic Hapludults; clayey, kaolinitic, thermic family) soil over a 3‐year period 1971‐73. In 1972 irrigation treatments were also included.No significant interactions were found between leaf characters, plant populations, N rates, and irrigation. Okra leaf shape increased earliness, boll size, and micronaire and decreased seed cotton loss due to boll rot. With increasing plant populations, lint yield and earliness tended to increase and boll size decreased. Higher boll rot loss was observed at higher levels of N. Irrigated cotton produced significantly greater lint yield, boll size, and fiber length and increased earliness.

Evaluation of Various Control Measures for Cotton Boll Rot

Evaluation of Various Control Measures for Cotton Boll Rot

NonInterference of Pseudomonas in the Bright, Greenish-Yellow (BGY) Fiber-Fluorescence Test for Aspergillus flavus Boll Rot

NonInterference of Pseudomonas in the Bright, Greenish-Yellow (BGY) Fiber-Fluorescence Test for Aspergillus flavus Boll Rot

Status of Cotton Boll Rot in the San Joaquin Valley of California Following Simulated Pink Bollworm Injury

Status of Cotton Boll Rot in the San Joaquin Valley of California Following Simulated Pink Bollworm Injury

Occurrence of Aflatoxins in Cotton Seeds at Harvest in Relation to Location of Growth and Field Temperatures

AbstractCotton seeds (Gossypium hirsutum L.) from 13 locations across the US Cotton Belt in 1969 and 11 locations in 1970 were analyzed for aflatoxins. Samples from most locations did not exhibit detectable aflatoxin contamination. However, aflatoxins B1 and B2 were found in one or more samples collected near Brawley, California; Phoenix, Arizona; and Weslaco, Texas, all in areas where a boll rot caused by Aspergillus flavus Link has been noted repeatedly since the crop of 1953. Aflatoxins occurred especially in seeds whose fiber exhibited a bright greenish yellow (BGY) fluorescence which is diagnostic for this boll rot. When seeds from the 1970 crop were examined for internal fungal infection, A. flavus was detected only in the seeds from Brawley. Free fatty acids were high in seeds from several areas, both with and without accompanying aflatoxins. Weather records indicated that A. flavus boll rot occurs mainly, perhaps exclusively, in conjunction with exceptionally high field temperatures.

Agronomic Potential of Nectariless Cotton

AbstractWe compared three BC6F4 nectariless strains of cotton (Gossypium hirsutum L.) with their recurrent parent varieties for yield, yield components, and fiber properties at six environments in 1971. A slight decrease (4.3%) in yield for nectariless ‘Stoneville 7A’ and a slight increase (3.8%) in yield for nectariless ‘Deltapine Smooth Leaf’ was detected. Nectaried and nectariless ‘Dixie King’ did not differ in yield. Nectariless strains, especially Deltapine Smooth Leaf tended to mature earlier. Slight but inconsistent differences in yield components of nectariless and nectaried strains were detected. Nectariless cottons tended to have shorter fibers.Significant genetic variability within BC6F3 nectariless populations of Stoneville 7A was detected, indicating that we were not working with isogenic nectariless varieties. Selection within BC5 nectariless Stoneville 7A resulted in yield improvement equal to that of nectaried Stoneville 7A. Fiber properties between nectaried and nectariless strains were essentially the same.The nectariless trait reduced boll rot. While the results from large field test were inconclusive, there were fewer tarnished plant bugs, fleahoppers, and less bollworm damage in nectariless cotton. Two predatory insects, lady beetles and big‐eyed bugs, were not affected by the presence or absence of nectaries.We detected no strong deleterious associations of nectariless and agronomic performance. This trait appears to have a good potential for insect and boll rot suppression in the Mississippi Delta.

A Boll Rot of Cotton Caused by Phytophthora parasitica

A Boll Rot of Cotton Caused by Phytophthora parasitica

Fungi That Infect Cottonseeds Before Harvest

As a part of an investigation of aflatoxins and other mycotoxins in cottonseeds at harvest, samples of seeds collected from the 1971 crop at locations across the U.S. Cotton Belt were examined to determine the kinds of microorganisms causing internal or seed-coat infection in the field. Aspergillus flavus infection was absent from all seeds examined from most areas but was present in some samples from Arizona, California, and Texas. Fusarium spp., Alternaria sp., and A. niger caused internal infection at many locations; Colletotrichum gossypii and Rhizopus stolonifer were present in seeds from some areas but were generally much less common. Many of the infections with A. niger were in the seed coat. Bacterial infections were fairly frequent. In a series of commerical samples from Arizona. A. flavus infection was found in 61% of seeds, with fiber showing the bright, greenish-yellow (BGY) fluorescence that is diagnostic for A. flavus boll rot. Aflatoxin contamination was also concentration in the same seeds. The above findings agree with previous data showing that aflatoxin contamination of cottonseeds before harvest occurs rarely, if at all, in most parts of the U.S. Cotton Belt and that when such contamination does occur, it tends to be concentrated in seeds with the BGY fluorescence in their fiber and seed fuzz.

Cotton Boll Cuticle, a Potential Factor in Boll Rot Resistance

Cotton Boll Cuticle, a Potential Factor in Boll Rot Resistance

Growth Analysis of American Upland Cotton, Gossypim hirsutum L., with Different Leaf Shapes and Colors1

Analysis of plant growth and development of biotypes of American Upland cotton (Gossypium hirsutum L.) with nine different combinations of leaf shape and color were made at two plant populations. The nine combinations of leaf shape and color were obtained by crossing Okra Leaf ‘Stoneville 7A’ BC4 with Red Leaf Stoneville 7A BC4 and then selecting the various leaf shapes and color combinations within the F2 population.Okra Leaf (L° L°) was associated with low incidence of boll rot, number of vegetative branches, node number of first‐fruiting branch, dry weight of vegetative parts, leaf area, and with a shorter plant compared with normal leaf type. Okra Leaf also resulted in earlier maturity, higher harvest index, and higher seed cotton yield compared with normal leaf cotton. Okra Leaf had no effect on fiber length or fiber length uniformity, but caused a slight reduction in fineness and a slight increase in fiber strength.The homozygous red color resulted in a significant reduction in seed cotton yield in an experiment with 45‐cm spacing within the row. There were no significant interactions between leaf shape and leaf color.All measurements for intermediate (heterozygous) leaf shape were between the values found for Okra Leaf and normal leaf cotton.

Effect of Temperature and Boll Injuries on Development of Diplodia Boll Rot of Cotton

Effect of Temperature and Boll Injuries on Development of Diplodia Boll Rot of Cotton

Effects of Bottom Defoliation on Microclimate and the Reduction of Boll Rot of Cotton1

AbstractIn 1963 and 1964, increases in boll rot of cotton were associated with short periods (5 to 7 days) of rainfall and, to a lesser extent the drying period following rainfall. Microclimate changes within the plant canopy associated with these periods indicate that increased duration of relative humidity at a level of 95% or higher, increased duration of free moisture, and reduced intensity of light, all favor boll rot development. Bottom defoliation reduced boll rot loss and modified the microclimate resulting in shorter duration of 95% or higher relative humidity; it increased light intensity in the lower plant zone, and possibly increased ventilation following periods of rainfall. Instrumentation used for microclimate measurements are described; and construction details of a simple mechanical psychrometer and a light intensity sensor‐recorder are presented.

Absorption and Movement of Benomyl into Cotton Bolls and Control of Boll Rot

Absorption and Movement of Benomyl into Cotton Bolls and Control of Boll Rot

Effects of Super Okra Leaf Shape on Boll Rot, Yield, and Other Characters of Upland Cotton, Gossypium hirsutum L.1

The effects of the super okra leaf shape on boll rot. yield, plant and fiber characters of Upland cotton, Gossypium hirsutum L., were investigated at three locations in Louisiana. Near isogenic populations of super okra leaf and normal leaf on each of three varietal backgrounds were used.Super okra leaf shape, as an average of varieties and locations, caused a significant reduction in boll rot, yield, fiber length, and total leaf surface area in comparison with normal leaf cotton. Super okra leaf shape caused an increase in earliness, lint percentage, fruiting rate, and micronaire value, but had no effects or inconsistent effects on boll size, fiber length uniformity, fiber strength, and fiber elongation. The interactions of variety ✕ leaf shape and location ✕ leaf shape were significant for some of the characters studied.A mixed population of super okra leaf and normal leaf plants in a 1:1 ratio was investigated. The mixed leaf population was found to have no advantage over the pure populations of the contrasting leaf shapes.

Fungal diseases of cotton plant <i>Gossypium hirsutum</i> L. in Bangladesh

Seven types of symptom were recorded in four varieties such as CB3, CB9, Hill cotton 1 (HC-1) and 2 (HC-2) of cotton (Gossypium hirsutum L.) during July, 2005 to June, 2008. The symptoms were Anthracnose, Alternnaria leaf spot, Boll rot, Cercospora leaf spot, Rust, Sclerotium rot and Wilting. Present study revealed that association of 30 species of fungi which belonged to 21 genera such as one one in Zygomycetes, one in Ascomycetes, one in Basidiomycetes, 18 in Deutermycetes and one in sterile fungus. The isolated fungi were Alternaria alternata (Fr.) Keissler, Arthrinium sp., Ascochyta sp., Aspergillus flavus, Link., Aspergillus niger Van Tiegh, Aspergillus sp., Botryodiplodia sp., Cercospora sp., Chaetomium sp., Chaetophoma sp., Cladosporium sp., Colletotrichun coffeanum Noack, z. f. Pflan zenko., Colletotrichum spp., Curvularia clavate Jain, Curvularia lunata (Wakker) Boedijn, Fusarium moniliforme, Wr. and Reink, Fusarium spp., Nigrospora sp., Pestalotia sp., Penicillium sp., Phoma sp., Pteroconium sp., Puccinia sp., Rhizopus stolonifer (Ehrenb. Ex. Fr) Lind, Sclerotium rolfsii Sacc., Trichoderma viride Pers. ex Fries. and one sterile fungus. Fusarium spp. and Colletotrichum spp. were frequently associated with all the four cotton varieties examined. Botryodiplodia sp. was associated with Hill Cotton 1 (HC-1) and Hill Cotton 2 (HC-2). Sclerotium rolfsii was found associated with CB-3 cotton variety. Key words: Fungal diseases; Cotton plant; Gossypium hirsutum; Bangladesh DOI: http://dx.doi.org/10.3329/dujbs.v20i2.8974 DUJBS 2011; 20(2): 139-146

Effects of Okra Leaf Shape on Boll Rot, Yield, and Other Important Characters of Upland Cotton, Gossypium hirsutum L.1

The effects of okra leaf shape on boll rot, yield, and other important characters of Upland cotton (Gossypium hirsutum L.), were investigated at three locations in Louisiana and on three varietal backgrounds. Varieties responded in a similar manner to the leaf shape treatments for all characters studied, but the location ✕ leaf shape interaction was significant in some cases.The okra leaf shape character, as an average of varieties and locations, caused a significant reduction in the incidence of boll rot in comparison with normal leaf cotton. It was associated with a significant increase in yield, earliness, lint percentage and micronaire value, and a substantial increase in fruiting rate. Okra leaf shape had no effect on boll weight, fiber length, fiber length uniformity, or fiber strength, but caused a reduction in fiber elongation and total leaf area.A mixed population of okra leaf and normal leaf plants in a 1:1 ratio was investigated. The mixed population was found to have no advantage over the pure populations of the contrasting leaf shapes.