Healthy Cotton Plants Research Articles

MACHINE LEARNING INTEGRATION, REMOTE SENSING DATA PREPROCESSING TECHNIQUES TO MAP PESTS COTTON CROPS

Cotton has a considerable economic impact on agribusiness. Strategies to reduce production loss due, for example, to pest attacks are increasingly required. Spodoptera frugiperda, known as fall armyworm, causes irreversible damage to cotton. In this context, a current approach is the use of hyperspectral measurements obtained by remote sensors and processed by machine learning algorithms. However, such measures generate data redundancy, making it difficult to extract information. An alternative is to apply pre-processing techniques, but little is known about the impact these generate on the learning ability of algorithms. This study evaluates the performance of machine learning algorithms in identifying cotton plants attacked by pests using pre-processed and raw hyperspectral measurements. Data are collected by EMBRAPA, and consist of hyperspectral measurements, in the range of 350-2500 nm, referring to eight days of collections in healthy cotton plants and attacked by S. frugiperda. Pre-processing techniques to try are baseline removal, smoothing, first and second order derivatives. A group of machine learning algorithms, such as Random Forest, Support Vector Machine, Extra Tree, was used to model pre-processed and non-pre-processed hyperspectral measurements. According to the proposed metric, the F-Score and the Extra Trees (ExT) algorithm performed better (0.77). So it overlapped the other results with the preprocessed dataset. In addition to obtaining the most important lengths for the algorithm to have its best performance. Concluding that machine learning with spectroscopy can help the field in a promising way. Studies in other crops and with other factors applied to the plant are recommended.

First Report of Alternaria alternata Causing Leaf Spot Diseases of Cotton in Türkiye.

Cotton (Gossypium hirsutum L.) is a crucial crop for the textile industry. Sanliurfa is the major cotton production area in southeast Türkiye (USDA 2021). In the summers of 2021 and 2022, the mid to late season desiccation of leaves, stems and bolls as well as severe defoliation were observed in different cotton fields and cultivars in a 30-ha area centered around 36°51'15.7"N, 39°07'12.2"E. Approximately 45% of the plants were severely affected or completely desiccated. Initially, symptoms were circular, pinhead, necrotic lesions surrounded by a purple halo, scattered all around the infected leaves. As the disease progressed, it spread to bracts, petioles, stem and bolls. The necrotic lesions continued to expand, and formed irregular shapes by coalescing, occupied the whole tissue . Finally, severe infection resulted in premature defoliation. A secondary host (Prosopis farcta) of the inoculum of A. alternata is found in the field where the symptoms of pathogen was seen. The disease symptoms were similar to those described in cotton by Macauley (1982). Infected leaf samples with mycelia were collected (n=35) from 25 diseased plants. The samples derived from lesions on infected leaves were cut into 4- to 5- mm pieces, treated in 2% sodium hypochlorite, dipped in water, plated on potato dextrose agar (PDA) amended with 30 mg/L of streptomycin sulphate, and kept at 27°C in the dark. All the isolated fungal samples formed dark olive-green colonies. For morphological characterization, the colonies were examined under light microscopy at ×400 magnification. Conidia formed both cross or longitudinal septa, and were obclavate to elliptical and measured 16.2 to 30.5 µm long and 7.5 to 10.6 µm wide (n=14). The morphological characters were consistent with the genus Alternaria using a taxonomic key (Barnett and Hunter 1972). For pathogenicity test, healthy cotton plants were grown at 15 to 29°C in greenhouse. Conidial suspension (10 6 per mL) was sprayed on 30-d old plants (n=16) while control plants were sprayed with water. Then, the plants were covered with plastic bags (28x45 cm) at nights, opened in the morning. The disease symptoms were seen 20 days after artificial inoculation. However, the control group showed no symptoms. The pathogen was re-isolated from infected leaves. To confirm the result, the pathogenicity test was conducted twice. Then, DNA was extracted from conidia and mycelia using CTAB method with slight modification (Doyle and Doyle 1990). The nuclear rDNA internal transcribed spacer (ITS) and plasma membrane ATPase regions were (Lawrence et al. 2014; White et al. 1990) amplified, using primers ITS4/ITS5 and ATPDF1/ATPDR1, respectively. The PCR products were Sanger-sequenced and were uploaded to GenBank (accession nos. ITS: OP615138.1, ATPase: OP612816.1). The sequenced parts of the genes were 554 bp and 1025 bp, and showed 100% (ITS) and 97.99% (ATPase) nucleotide identity with the corresponding sequences (MT446176.1, ON442363.1) of the reference strains of A. alternata. To the best of our knowledge, this is the first report of A. alternata causing leaf blight of cotton in Türkiye. In several cotton-growing regions, A. alternata leaf spot epidemics have caused yield loss from 25% (Israel) to 37% (India) (Padaganur et al. 1989; Rotem et al. 1988). Although yield loss caused by the pathogen depends on environmental conditions, observations in Türkiye cotton fields suggest A. alternata has the potential to cause yield loss up to 30% under severe infection.

Detection of Brasiliomyces malachrae Causing Powdery Mildew on Ornamental Cotton (Gossypium hirsutum) plants in Mexico.

Cotton (Gossypium L.; Malvaceae) is the most important fiber crop worldwide, also as a source of vegetable protein and edible oil. Cultivated species of cotton were apparently domesticated independently in four separate regions, in both the Old and the New World. Due to its economic importance, it is necessary to study the diseases that limit its production. During July of 2020-2022, symptoms of powdery mildew were observed on 80 ornamental cotton plants in a nursery located in Cuautla (18°52'38"N; 98°58'28"W), Morelos, Mexico. Disease incidence was 29%. Signs first appeared as small white colonies, which subsequently developed into abundant mycelial grown mainly on the upper leaf surface. White patches of mycelia were observed on leaves. In advanced stages of the disease, plants exhibited symptoms of yellowing, necrosis, and early defoliation. Microscopic analysis from 10 plant samples showed that mycelia were amphigenous, epiphyllous, in thin patches and evanescent. Hyphae were hyaline, thin walled and hyphal appressoria were simply lobed. Chasmothecia (n=50) were sub-aggregate, generally spherical to subglobose (46-61 µm in diameter), whitish, subhyaline, smooth, with a peridium of a single cell layer and appendages were absent. Three asci per chasmothecia, subspherical, 30-44 × 26-38 µm, with 4-6 ascospores per ascus. Ascospores were hyaline, ellipsoid to ovoid (16-23 × 10-18 µm). The asexual phase was not observed. The characteristics observed correspond to Brasiliomyces malachrae (Braun and Cook 2012; Cabrera et al. 2018). A voucher specimen was deposited in the Herbarium of the Department of Plant-Insect Interactions at the Biotic Products Development Center of the National Polytechnic Institute under accession no. IPN 10.0114. To confirm identification, DNA was recovered from the fungus and the internal transcribed spacer (ITS) from one sample was amplified by PCR, using the primers ITS1/ITS4 (White et al. 1990). The sequence was deposited in GenBank (OQ546720) and showed 100% sequence homology (647/1642bp) with the type sequence of B. malachrae (LC191217) from Malvastrum coromandelianum in Argentina (Cabrera et al. 2018). Pathogenicity was verified through inoculation by gently dusting conidia from infected leaves onto leaves of five healthy cotton plants. Five noninoculated plants served as controls. All plants were maintained in a greenhouse at temperatures from 28±2°C and relative humidity ranging from 80±5%. The experiment was performed twice. Inoculated plants developed powdery mildew symptoms after 14 days, whereas the control plants remained healthy. The fungus on the inoculated leaves was morphologically identical to that originally observed on diseased plants, thus fulfilling Koch's postulates. To our knowledge, this is the first report of Brasiliomyces malachrae causing powdery mildew on Gossypium hirsutum in Mexico and North America (Farr and Rossman 2023). Powdery mildew on G. hirsutum caused by B. malachrae has been previously identified in Venezuela by Hanlin and Tortolero (1984). This disease could be a primary source of inoculum of powdery mildew for commercial cotton plantations, derived from the free movement of ornamental plants.

Volatiles from Cotton Plants Infested by Agrotis segetum (Lep.: Noctuidae) Attract the Larval Parasitoid Microplitis mediator (Hym.: Braconidae).

Herbivore-induced plant volatiles (HIPVs), chemicals produced by plants infested by herbivorous insects, can act as kairomones that recruit natural enemies of the pest herbivore. Agrotis segetum (Denis and Schiffermüller) is a common, important pest of seedling cotton in Xinjiang Province, China, and the braconid Microplitis mediator (Haliday) is an important mortality factor of this pest’s larvae. In olfactometer tests, which included healthy foliage, infested foliage, or infested roots, M. mediator preferred A. segetum-infested cotton plants to healthy cotton plants. In GC-MS analyses of plant-emitted volatiles, we found that compounds emitted increased 14.9- and 13.3- fold after leaf infestation and root infestation, respectively, compared to healthy control plants. The volatiles were mainly p-xylene, nonanal, tetradecane, decanal, benzaldehyde, β-caryophyllene, and humulene, while linalool was only present in the leaf-infestation treatment. In addition, principal component analysis indicated that all 18 compounds were associated with the infested plants, especially β-caryophyllene, p-xylene, and decanal. Based on the above studies and previous functional evaluations of the volatile compounds, it can be demonstrated that these compounds play a crucial role in modulating the interactions between A. segetum and M. mediator and regulating parasitoid behavior. It may be possible to enhance the biological control of A. segetum by M. mediator through the application of HIPVs.

Adsorbent-SERS Technique for Determination of Plant VOCs from Live Cotton Plants and Dried Teas.

We developed a novel substrate for the collection of volatile organic compounds (VOCs) emitted from either living or dried plant material to be analyzed by surface-enhanced Raman spectroscopy (SERS). We demonstrated that this substrate can be utilized to differentiate emissions from blends of three teas, and to differentiate emissions from healthy cotton plants versus caterpillar-infested cotton plants. The substrate we developed can adsorb VOCs in static headspace sampling environments, and VOCs naturally evaporated from three standards were successfully identified by our SERS substrate, showing its ability to differentiate three VOCs and to detect quantitative differences according to collection times. In addition, volatile profiles from plant materials that were either qualitatively different among three teas or quantitatively different in abundance between healthy and infested cotton plants were confirmed by collections on Super-Q resin for dynamic headspace and solid-phase microextraction for static headspace sampling, respectively, followed by gas chromatography to mass spectrometry. Our results indicate that both qualitative and quantitative differences can also be detected by our SERS substrate although we find that the detection of quantitative differences could be improved.

Evaluation of the Biocontrol Potential of Endophytic Fungus Fusarium solani CEF559 against Verticillium dahliae in Cotton Plant.

Verticillium wilt of cotton, caused by the soilborne pathogen Verticillium dahliae, is one of the most serious diseases of cotton worldwide. Increased concerns about the side effects of synthetic pesticides have resulted in greater interest in developing biocontrol strategies against Verticillium wilt. We evaluated a Fusarium solani CEF559 isolate, obtained from the endosphere of healthy cotton plants, for its biocontrol potential against V. dahliae in vitro and in vivo. In addition to disease assessment, three key genes in the lignin metabolism pathway and four pathogenesis-related (PR) genes were monitored using qRT-PCR. In the laboratory tests, F. solani CEF559 inhibited V. dahliae colony growth by 75% and sporulation by nearly 80% and completely suppressed conidial production. However, volatile metabolites from CEF559 did not affect V. dahliae colony growth. In the greenhouse study, CEF559 significantly reduced wilt development, with a control efficacy greater than 60% when assessed 25 days postinoculation. In a field experiment, CEF559 reduced wilt development, with the efficacy ranting from 30.1% to 56.3%. PR genes and those key genes in the lignin metabolism pathway were transiently upregulated in the cotton roots pretreated with CEF559 when subsequently inoculated with V. dahliae, compared with those plants inoculated with V. dahliae only. Moreover, CEF559 inhibited V. dahliae colonisation of both the roots and hypocotyls. The present results suggest that this cotton endophytic fungal strain, F. solani CEF559, confers protection against V. dahliae.

Diversity and antiviral potential of rhizospheric and endophytic Bacillus species and phyto-antiviral principles against tobacco streak virus in cotton

Plant growth promoting rhizobacteria arewidely exploited for the management of various fungal and bacterial diseases in plants. However, antiviral action of PGPR and their efficiency have been rarely investigated. In the present study, influential diversity of Bacillus species was related with tobacco streak virus (TSV) infection in cotton. The study revealed that, the population of B. subtilis, B. licheniformis and B. velezensis in rhizosphere of apparently healthy cotton plants were comparatively higher than TSV infected plants, indicating that they efficiently colonized the rhizosphere. Similarly, the population of the endophytic B. cereus and B. licheniformis were relatively higher in apparently healthy than TSV infected cotton plants. In vitro screening of rhizospheric, endophytic Bacillus species and phyto-antiviral principles revealed that rhizospheric B. amyloliquefaciens (VB7) and endophytic B. licheniformis (CoEH6) were effective in the suppression of TSV symptoms in indicator host (cowpea). The strain B. amyloliquefaciens (VB7) contained ten antimicrobial peptide genes responsible for the biosynthesis of antibiotics including, iturin, bacilysin, bacillomycin, surfactin, subtilin, and subtilosin. Moreover, the strain VB7 is reported to secrete pentadecenoic acid, heptadecenoic acid, octadecenoicacid, pyrrolo, piperazinedione and tetradecenoic acid, which would have together complemented in the antiviral activity. Upon simultaneous inoculation of the bacterium or phyto-antiviral principles with TSV in the indicator host plant, revealed that B. amyloliquefaciens (VB7) and M. jalapa were much effective and reduced the number of lesions up to 2.22/leaf and 3.00/leaf respectively compared with TSV inoculated control (25.28 lesions cm−2 area). Further, under field conditions, soil application and foliar spray of the B. amyloliquefaciens (VB7) resulted in 52 per cent reduction in TSV incidence. For reference TSV incidence in B. amyloliquefaciens (VB7) treated and untreated plots were 21.67 (PDI) and 45 (PDI) respectively. Moreover, B. amyloliquefaciens (VB7) improved seed cotton yield upto 149.45 g/plant compared to control (97.71 g/plant). Thus B. amyloliquefaciens (VB7) was exploited as an efficient antagonist for the management of TSV in cotton.

Induction of phenylalanine ammonia-lyase (PAL) in insect damaged and neighboring undamaged cotton and maize seedlings

ABSTRACTThere has been scepticism about plants responding to information from their damaged neighbor plants since it was first reported, although a growing body of evidence indicates that interplant communication may play a key role in the resistance of plants. Cotton aphids and corn borer are important insects in cotton and maize, respectively. The resistance of healthy cotton and maize plants induced by their neighbor damaged plants was investigated in this study. Phenylalanine ammonia-lyase (PAL) is a chemical marker of induced resistance in many plants. The enzymatic activity and gene expression of PAL were determined in cotton and maize seedlings damaged by wounding, aphid and corn borer attack and in intact undamaged maize and cotton seedlings growing nearby. The enzymatic activity and gene expression of PAL were significantly increased in the cotton and corn seedlings damaged by wounding or by aphid and corn borer. Furthermore, undamaged neighboring cotton and maize seedlings also showed elevated enzymatic activity and gene expression of PAL. These inductions of PAL enzymatic activity and gene expression in the damaged and undamaged seedlings suggest inter-species communication between cotton and maize.

Identification and application of biocontrol agents against Cotton leaf curl virus disease in Gossypium hirsutum under greenhouse conditions

ABSTRACTBiological control is a novel approach in crop protection. Bacteria, such as Bacillus spp. and Pseudomonas spp., are reported for this purpose and some of their products are already commercially available. In this study, the rhizosphere and phyllosphere of healthy cotton plants were used as a source of bacterial isolates with properties of potential biocontrol agents. The isolates were screened for phosphate solubilization activity, indole acetic acid (IAA) production and antifungal activity. Two isolates, S1HL3 and S1HL4, showed phosphate solubilization and IAA production simultaneously, while another two, JS2HR4 and JS3HR2, demonstrated potential to inhibit fungal pathogens. These bacteria were identified as Pseudomonas aeruginosa (S1HL3), Burkholderia sp. (S1HL4) and Bacillus sp. (JS2HR4 and JS3HR2) based on biochemical and molecular characteristics. The isolates were tested against Cotton leaf curl virus (CLCuV) in greenhouse conditions, both as individual bacterial isolates and consortia. Treated plants were healthy as compared to control plants, where up to 74% of the plants were symptomatic for CLCuV infection. Maximum inhibition of CLCuV was observed in the plants treated with a mixture of bacterial isolates: the viral load in the treated plants was only 0.4% vs. up to 74% in controls. This treatment consortium included P. aeruginosa S1HL3, Burkholderia sp. S1HL4 and Bacillus spp. isolates, JS2HR4 and JS3HR2. The principal-component biplot showed a highly significant correlation between the viral load percentage and the disease incidence.

Effect of Cotton leaf curl virus infected plants on the biology of the whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae): Vector–virus mutualism

Cotton leaf curl virus (CLCuV) (Geminiviridae : Begomovirus), the causative agent of leaf curl disease in cotton plants (Gossypium hirsutum), is exclusively transmitted by whitefly species Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). CLCuV transmission occurs in Sriganganagar (Rajasthan), an area endemic with cotton leaf curl disease. The relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. To further understand these relationships, fecundity and life history parameters of an indigenous non- b (Asia II genetic group) biotype whitefly, B. tabaci, were compared on 10, 25, and 40 days post-inoculation (DPI), in CLCuV-infected and healthy cotton plants to determine the effect of virus on its vector. The development time of the immature stages of whiteflies was significantly reduced on CLCuV-infected plants. The development time of the immature stages did not change with severity of symptoms at 25 and 40 DPI (45- and 60-d-old plants). Cotton leaf curl virus infection increased percent egg viability of B. tabaci. Whiteflies deposited significantly fewer eggs on virus-infected plants than on healthy plants. Whiteflies had better egg viability on younger plants than older plants, whereas plant age did not affect the fecundity. Male and female whiteflies had shorter longevity on CLCuV-infected plants than on healthy plants.

First Report of Nigrospora oryzae Causing Leaf Spot of Cotton in China.

Cotton (Gossypium hirsutum L.) is widely cultivated for the important economic value of the fiber. In the summer of 2011, a leaf spot of cotton plants cv. Wanza40 was observed in 11 fields (total of about 4 ha) in Qianshan County in southwest Anhui Province, China. Approximately 30% of the plants in each field were symptomatic. Affected plants exhibited brown to reddish, irregular foliar lesions, each with a brown border near the vein of the leaves. A sign of fungal infection was a dark leaf mold observed on lesions on the abaxial surface of leaves. Sections of symptomatic leaf tissues were surface-sterilized (in 75% ethanol for 30 s, then 1% NaOCl for 1 min), rinsed three times in sterile distilled water, and plated onto potato dextrose agar (PDA). A fungus consistently recovered from symptomatic leaf samples produced colonies that were initially white and then became grayish brown with the onset of sporulation. Black, spherical to subspherical, single-celled conidia (10 to 12 × 14 to 16 μm) were borne on a hyaline vesicle at the tip of each conidiophore. Morphological characteristics of the fungus were similar to that of Nigrospora oryzae (2). The internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) from a representative strain of the fungus, AHC-1, was amplified using the primers ITS1/ITS4 (4) and sequenced (GenBank Accession No. JQ864579). The ITS sequence had 99% identity with >553 bp of the ITS sequence of an N. oryzae isolate (GenBank Accession No. EU918714.1). On the basis of morphological data and ITS rDNA sequence, the isolate was determined to be N. oryzae. A pathogenicity test was performed on detached, young leaves of 4-month-old healthy cotton plants of cv. Wanza40. Six leaves were inoculated by placing a colonized agar piece (5 mm in diameter) from 7-day-old cultures of the fungus on pushpin-wounded leaves. Another six leaves treated with sterile PDA plugs served as a negative control treatment. Leaves were incubated in petri dishes and maintained at 25°C in a growth chamber programmed for 12 hours of fluorescent white light/day. After 5 days, brown to black lesions were observed on all inoculated leaves, whereas no symptoms developed on control leaves. N. oryzae was consistently reisolated from symptomatic leaves but not from the control leaves. N. oryzae is a weak pathogen on a wide range of plants, and has been described as the causal agent of lint rot on cotton (1,3), but to our knowledge this is the first report of N. oryzae causing a leaf spot of cotton in China.

Settling preference of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) on healthy versus cotton leaf curl virus-infected cotton plants

Cotton leaf curl disease, a viral infection vectored by the whitefly Bemisia tabaci (Gennadius), is a major threat to the cotton industry in India and Pakistan. We examined the settling preferences of B. tabaci adults on infected versus healthy cotton plants under choice conditions. For experiments with plants at 20 and 35 days post-inoculation (DPI), whiteflies preferentially settled on healthy cotton plants after 8 and 1 h of release, respectively. Whiteflies, however, were unable to discriminate between virus-infected and healthy cotton plants at 5 DPI. Our results suggest that whiteflies' preference for healthy plants compared with diseased plants can lead to rapid virus spread in the field, resulting in higher crop losses.

Performance of Bemisia tabaci (Hemiptera: Aleyrodidae) on Healthy andCotton Leaf Curl VirusInfected Cotton

Abstract Cotton leaf curl virus (CLCuV) is a group of whitefly-transmitted Geminiviruses that cause extensive damage to cotton in India and Pakistan. Begomoviruses have a complex association with their whitefly vector. To further understand these relationships, fecundity and life history parameters of Bemisia tabaci (Gennadius) were compared on 5, 20, 35 d post inoculated (DPI), CLCuV infected and healthy cotton plants to determine the effect of virus on its vector. Cotton leaf curl virus infection increased percent egg viability of B. tabaci. Whiteflies deposited significantly fewer eggs on virus infected plants compared to healthy plants. The development time of whiteflies from egg to adulthood was significantly reduced on CLCuV infected plants with shorter nymphal and pupal duration. Male and female whiteflies had shorter longevity on CLCuV infected plants compared with healthy plants. The egg duration was similar on CLCuV infected and healthy plants regardless of DPI of plants.

Acquisition and Transmission of two Begomoviruses by the B and a non‐B Biotype of Bemisia tabaci from Zhejiang, China

AbstractAcquisition and transmission was studied of Tomato yellow leaf curl China virus (TYLCCNV) and Tobacco curly shoot virus (TbCSV) by the B and a non‐B biotype (China‐ZHJ‐1) of Bemisia tabaci from Zhejiang, China. The frequency of TYLCCNV and TbCSV detection by PCR in whitefly adults increased with increasing length of feeding on virus‐infected plants. The virus DNA was detected by PCR in 40% of the B biotype adults tested after a period of 30 min access to infected plants and in all adults after a 12‐h period of access. All ZHJ‐1 adults acquired TYLCCNV and TbCSV after a 48‐h period of access to the virus‐infected plants. Viruliferous B and ZHJ‐1 adults retained TYLCCNV DNA for their entire life when placed on healthy cotton plants. Viruliferous ZHJ‐1 adults retained TbCSV DNA for their entire life when placed on healthy cotton plants but the B biotype adults did not. Transmission of TYLCCNV was achieved with one B or ZHJ‐1 adult per plant, and the probability of transmission reached 100% when the number of adults was increased to 10 per plant. The efficiency for TYLCCNV transmission to healthy plants by adults of both B and ZHJ‐1 was much higher than that for TbCSV.

Bacillus endophyticus sp. nov., isolated from the inner tissues of cotton plants (Gossypium sp.).

Four strains of aerobic, endospore-forming bacteria were isolated from the inner tissues of healthy cotton plants (Gossypium sp., Dushanbe, Tajikistan). The organisms had identical randomly amplified polymorphic DNA patterns that distinguished them from other bacilli that are commonly isolated from plant tissues, e.g. Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus pumilus and Bacillus subtilis. PCR amplification of 16S-23S rRNA spacer regions suggested that the four strains could be assigned to two highly related taxa, which correlated with differences in cell morphology. However, the cloned spacer region provided a simple and specific hybridization probe for all four strains. The virtually complete 16S rDNA sequences were prepared for representatives of the two groups (strains 2DT(T) and 12DX) and differed by only two bases, thus supporting classification of the four strains in a single taxon at the species level. Phylogenetic analyses indicated that strain 2DT(T) belonged to the genus Bacillus and was most closely related to Bacillus sporothermodurans DSM 10599T with a sequence similarity of 94.8%. It is concluded that the four strains belong to a novel species of Bacillus for which the name Bacillus endophyticus sp. nov. is proposed. The type strain is 2DT(T) (= UCM B-5715T = CIP 106778T).

AUTOMATED AIR PHOTO INTERPRETATION IN THE MAPPING OF SOIL SALINIZATION IN COTTON-GROWING ZONES

The paper describes efforts by a research team to automate methods of air photo interpretation in order to speed up and make more objective the interpretation process in compiling maps of soil salinization. The basic (inductive) approach involved the determination of spectral brightness coefficients and image photodensities for areas known to have specific characteristics with respect to relative areas of healthy and dead cotton plants and soil salinity. Attention is then devoted to the use of these relationships in algorithms used to discriminate saline, nonsaline, and mixed (saline/nonsaline) areas. Translated by Edward Torrey, Alexandria, VA 22308 from: Aerokosmicheskiye metody v pochvovedenii i ikh ispol'zovaniye v sel'skom khozyaystve: sbornik nauchnykh trudov [Remote Sensing Methods in Soil Science and Their Utilization in Agriculture: A Collection of Scientific Works]. Moscow: Nauka, 1990, pp. 226–231.

Aminomethylation of dioxane lignins of healthy and wilt-diseased cotton plants of the variety Tashkent-1

The products of the aminomethylation of dioxane lignins of healthy and wilt-diseased plants of variety Tashkent-1 according to the vegetation periods (ADLKhT-1-VII) have been studied. It has been established that the dioxane lignins of the wilt-diseased cotton-plant stems are less condensed.

Lipid composition of the seeds of the cotton plant infected with wilt

The qualitative and quantitative set of lipid components of the seeds of healthy cotton plants of the variety Tashkent-1 and plants infected with verticillium wilt have been studied. It has been established that the compositions of the lipids of the two samples differ considerably. The greatest differences are observed in the amounts of total lipids, gossypol, and low-molecular-weight volatile acids.

A study of the structure of lignins of healthy and wilt-affected cotton plants of the variety Tashkent-1

Continuing a study of the dioxiane lignins of healthy and wilt-affected cotton plants of variety Tashkent-1 (DLCT) according to vegetation period, we have performed nitrobenzene oxidation and cleavage with sodium in liquid ammonia of the natural and isolated dioxane lignins. It has been established that in the wilt-affected samples of cotton-plant stems the amount of guaiacyl and syringyl structural units increases.

An investigation of the lignins of healthy and wilt-affected cotton plants of variety Tashkent-1 according to the vegetation periods

1. The dioxane lignins of healthy and wilt-affected cotton plants of variety Tashkent-1 have been isolated and have been studied comparatively in relation to the vegetation period. On the basis of elementary and functional analysis, semiempirical formulas of the dioxane lignins isolated (DLCT-I to -VII) have been determined and it has been established that the dioxane lignins isolated from the wilt-affected plants contain more OCH3 groups per phenyl-propane structural unit than the lignins of healthy plants.