scholarly journals Impacts of Verticillium Wilt on Photosynthesis Rate, Lint Production, and Fiber Quality of Greenhouse-Grown Cotton (Gossypium hirsutum)

Plants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 857
Author(s):  
Addissu G. Ayele ◽  
Terry A. Wheeler ◽  
Jane K. Dever
Keyword(s):  
Verticillium Wilt ◽  
Photosynthetic Rate ◽  
Fiber Quality ◽  
Short Fiber ◽  
Fiber Content ◽  
Photosynthesis Rate ◽  
Breeding Lines ◽  
Fiber Properties ◽  
Cotton Genotypes ◽  
Disease Pressure

Verticillium wilt, caused by Verticillium dahliae Kleb., leads to significant losses in cotton yield and fiber quality worldwide. To investigate Verticillium wilt impact on photosynthesis rate, yield, and fiber quality, six upland cotton genotypes, namely Verticillium susceptible (DP 1612 B2XF) and partially resistant (FM 2484B2F) commercial cultivars and four breeding lines, were grown to maturity under greenhouse conditions in soil either infested or not infested with V. dahliae microsclerotia. Photosynthetic rate, lint, and seed yield were all higher (p < 0.05) for FM 2484B2F than DP 1612 B2XF when infected with V. dahliae. When comparing healthy (H) to Verticillium wilt (VW) affected plants, fiber properties were greatly impacted. Micronaire decreased from 5.0 (H) to 3.6 (VW) with DP 1612 B2XF and 4.4 (H) to 4.1 (VW) with FM 2484B2F. The maturity ratio decreased from 0.90 (H) to 0.83 (VW) for DP 1612 B2XF and was unchanged for FM 2484B2F (0.90). Fiber properties such as short fiber content, nep count, fineness, and immature fiber content were also significantly affected under Verticillium wilt pressure. With Verticillium wilt affected plants, lines 16-13-601V and 17-17-206V performed similarly to FM 2484B2F for photosynthetic rate, yield, and all fiber properties measured. When selecting for improved cultivars in the presence of Verticillium wilt, it is important to select for relatively unchanged fiber properties under disease pressure in addition to reduced disease severity and increased yield.

scholarly journals Use of Pressured-Air for Cotton Lint Cleaning

2019 ◽  
Vol 12 (1) ◽  
pp. 31
Author(s):  
Ruixiu Sui
Keyword(s):  
Cotton Fiber ◽  
Fiber Length ◽  
Fiber Quality ◽  
High Volume ◽  
Short Fiber ◽  
Fiber Content ◽  
Mechanical Contact ◽  
Cotton Lint ◽  
Fiber Properties ◽  
Cotton Fiber Quality

Saw-type lint cleaner (STLC) was most efficient lint cleaner in cotton ginning. However, STLC damaged fiber quality. An air-bar lint cleaner (ABLC) was developed and evaluated to preserve cotton fiber quality. The ABLC used pressurized-air to remove non-lint materials from cotton fiber. During lint cleaning process, non-lint materials attached to the fiber were blown off the fiber without the fiber making aggressive mechanical contact with a grid bar in conventional saw-type lint cleaner (STLC). It was expected using this concept that the fiber quality could be preserved by reducing the damage from mechanical impact of the fiber against the grid bar. Preliminary testing of the ABLC prototype showed that ABLC generated less lint waste and had a higher turnout rate than STLC. Use of ABLC could save 2.8 kg of lint in each 225 kg bale of cotton. The High Volume Instrument (HVI) analysis indicated the fiber properties in fiber length, uniformity, short fiber content, and color were not significantly different between ABLC and STLC. However, the Advanced Fiber Information System (AFIS) tests showed STLC had better performance than ABLC in fiber length and short fiber content while the trash and dust content with ABLC was lower than the STLC. More research was necessary to further prove the concept of ABLC and improve its performance in preserving cotton fiber quality.

scholarly journals Determination of Tolerance Levels of Cotton Genotypes Obtained from F6-F7 Generation against Verticillium Wilt Disease Caused by Verticillium dahliae Kleb.

2013 ◽  
Vol 41 (1) ◽  
pp. 184
Author(s):  
Oktay EROÄžAN ◽  
Emine KARADEMIR ◽  
Çetin KARADEMIR ◽  
Aydın UNAY
Keyword(s):  
Verticillium Wilt ◽  
Verticillium Dahliae ◽  
Fiber Strength ◽  
Disease Index ◽  
Cotton Yield ◽  
Seed Cotton ◽  
Breeding Lines ◽  
Seed Cotton Yield ◽  
Cotton Genotypes ◽  
Verticillium Dahliae Kleb

The susceptibility of cotton genotypes obtained from F6 and F7 generations to Verticillium wilt (VW) disease (Verticillium dahliae Kleb.), was studied under artificial and natural infestation during 2009 and 2010 growing seasons at the Cotton Research Institute’s, Nazilli, Aydın, Turkey. In this study, fifteen cotton breeding lines and two control varieties were used as plant material. During the cotton growing season, foliar disease index (FDI), vascular disease index (VDI) and pot disease index (PDI) were observed in addition to seed cotton yield and some fiber quality characteristics. According to the obtained results, disease severity (DS) values observed in pot experiments were higher than field trials. In terms of DS, ‘Tamcot CD3H’ × ‘Tamcot Luxor-III’, ‘Maraş92’ × ‘Tamcot Sphinx’ and ‘Sayar 314’ × ‘Stoneville 453-I’ breeding lines exhibited similar values with tolerant ‘Carmen’ variety. ‘Tamcot CD3H’ × ‘Tamcot Sphinx’, ‘Sayar 314’ × ‘Stoneville 453-I’, ‘Sayar 314’ × ‘Stoneville 453-II’ and ‘Stoneville 453’ × ‘Tamcot Sphinx’ breeding lines which gave similar DS values with tolerant ‘Carmen’ variety were statistically on the same group with ‘Carmen’ variety suitable to seed cotton yield. In this study, the disease tolerant breeding lines had higher fiber strength values than susceptible lines, the lowest fiber strength value obtained from ‘Cukurova 1518’ susceptible variety.

scholarly journals Differential Morphophysiological and Biochemical Responses of Cotton Genotypes Under Various Salinity Stress Levels During Early Growth Stage

2021 ◽  
Vol 12 ◽  
Author(s):  
Wajeeha Munawar ◽  
Amjad Hameed ◽  
Muhammad Khashif Riaz Khan
Keyword(s):  
Salt Tolerance ◽  
Salinity Stress ◽  
Photosynthetic Rate ◽  
Plant Biomass ◽  
Fiber Quality ◽  
Enzymatic Antioxidants ◽  
Cotton Production ◽  
Cotton Genotypes ◽  
Mda Content ◽  
Series Of Experiments

Cotton is a primary agriculture product important for fiber use in textiles and the second major oil seed crop. Cotton is considered as moderately tolerant to salt stress with salinity threshold of 7.7 dS/m at seedling stage. Salinity causes reduction in the growth of seedlings and cotton production that limits fiber quality and cotton yield. In this study, initially, 22 cotton genotypes were screened for relative salt tolerance using germination test in Petri plates (growth chamber). Selected 11 genotypes were further tested in pot experiment (sand) with 0, 15, and 20 dS/m NaCl treatments under glass house conditions. At four-leaves stage, different morphological and physiological traits were measured for all genotypes while biochemical analysis was performed on selected seven highly tolerant and sensitive genotypes. NaCl treatment significantly reduced plant biomass in two genotypes IR-NIBGE-13 and BS-2018, while NIAB-135, NIAB-512, and GH-HADI had least difference in fresh weight between the control and NaCl-treated plants. Photosynthetic rate was maintained in all the genotypes with the exception of SITARA-16. In two sensitive genotypes (IR-NIBGE-13 and 6071/16), Na+ ion accumulated more in leaves as compared to K+ ion under stress conditions, and an increase in Na+/K+ ratio was also observed. The lesser accumulation of malondialdehyde (MDA) content and higher activity of enzymatic antioxidants such as superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) in stressed plants of NIAB-135, NIAB-512, and FH-152 indicated that these genotypes had adaption capacity for salinity stress in comparison with sensitive genotypes, i.e., IR-NIBGE-13 and 6071/16. The observed salt tolerance was corelated with plant biomass maintenance (morphological), photosynthetic rate, and ionic homeostasis (K+/Na+ ratio, physiological) and biochemical stress marker regulations. After a series of experiments, it was concluded that NIAB-135, NIAB-512, and FH-152 could be utilized in breeding programs aimed at improving salinity tolerance in cotton and can expand cotton cultivation in saline area.

Microsatellite-based characterization of cotton genotypes for verticillium wilt and fiber quality traits

2017 ◽  
Vol 43 (3) ◽  
pp. 277-288
Author(s):  
Amna Saeed ◽  
Eminur Elçi
Keyword(s):  
Genetic Diversity ◽  
Ssr Markers ◽  
Verticillium Wilt ◽  
Fiber Quality ◽  
Stress Factors ◽  
Quality Traits ◽  
Cotton Yield ◽  
Fiber Quality Traits ◽  
Resistant Cultivars ◽  
Cotton Genotypes

Abstract Cotton (Gossypium hirsutum L.) is the most important natural textile fiber crop grown worldwide. Several biotic and abiotic stress factors affect cotton yield due to lower genetic diversity for the traits of particular interest. Verticillium wilt (VW) is one of the major factors incurring huge cotton yield losses. The most effective management option against VW is the development of resistant cultivars. The resistant cultivars must also have superior fiber quality and yield traits. Therefore, the current study was aimed at screening some of the identified simple sequence repeats (SSR) markers for VW resistance and fiber quality traits of cotton genotypes in Turkey. Fifty different cultivars were screened with 30 SSR markers. Polymerase chain reaction (PCR) was conducted to amplify the SSR markers. The amplified bands were scored as 0 or 1 for absence and presence, respectively. For the molecular data analysis, polymorphism information content (PIC) values of molecular markers were calculated. Among tested SSR markers 13 were found polymorphic, which produced a total of 677 loci. The number of alleles per marker ranged from 1 to 4 and, overall average PIC values of markers ranged from 0.00 to 0.76, respectively. Principal component analysis executed on presence absence data yielded two distinct groups of cultivars screened. Hierarchical clustering revealed low genetic diversity among the tested cultivars. Based on the results TamcotCamdES, Gloria, Natalia, Lydia, Teks, Tamcot SP37H, N87 and BA525 are the promising cultivars for further breeding studies. The results of the current study also revealed that 4 SSR markers (DPL752 and DPL322 for fiber traits, DPL0022 and GH215 for VW resistance) out of 30 could be used for improving VW resistance and fiber quality in cotton through marker assisted selection.

“Regressional” Observations of HVI Fiber Properties, Yarn Quality, and Processing Performance of Medium Staple Cotton

1992 ◽  
Vol 62 (4) ◽  
pp. 218-226 ◽  
Author(s):  
Yehia E. El Mogahzy ◽  
Roy M. Broughton
Keyword(s):  
Multivariate Analyses ◽  
High Volume ◽  
Short Fiber ◽  
Fiber Content ◽  
Empirical Equations ◽  
Fiber Properties ◽  
Yarn Quality ◽  
Correlation Analyses ◽  
Wide Range ◽  
Fiber Maturity

Fiber data (USDA) representing six cotton crops (1984–1989) were analyzed using regression and correlation analyses. These data consist of two high volume instrument systems (MCI and SpinLab) fiber properties and corresponding properties measured by traditional systems (the Suter-Webb array method, the Peyer Almeter, the Shirley FMT, the Shirley trash analyzer, and the Pressley strength tester). Different testing systems were compared using bivariate and multivariate analyses, and empirical equations for predicting fiber maturity and short fiber content suggested. The reliability of the results shown in this study is driven by the fact that the data examined involve a wide range of varieties and properties and a large number of observations.

scholarly journals Characterization of Egyptian Cotton Fiber Quality Using CCS

2021 ◽  
Vol 3 (1) ◽  
pp. 45-52
Author(s):  
Mona El-Sayed Shalaby ◽  
Ibrahim Ahmed Ebaido ◽  
Yasser Shokry Abd-El-Rahman
Keyword(s):  
Confidence Intervals ◽  
Cotton Fiber ◽  
Agricultural Research ◽  
Fiber Quality ◽  
Short Fiber ◽  
Sample Sizes ◽  
Fiber Properties ◽  
Growing Seasons ◽  
Global Center ◽  
Egyptian Cotton

The purpose of the current study is to characterize Egyptian cotton using HVI and CCS measurements. The present investigation was carried out at two different locations: The Global Center for Cotton Testing Research in International Cotton Association (ICA) using HVI instrument in Germany and Egyptian and International Cotton Classification Center (EICCC), Cotton Research Institute (CRI), Agricultural Research Center (ARC) using CCS instrument in Egypt. Samples are sourced from standardized preparation stages to obtain more homogeneity. All samples were collected from 2018 and 2019 cotton growing seasons. The studied cotton fiber properties: upper half mean (UHM), uniformity index (UI %), short fiber index (SFI %), strength (FS) and elongation (E %) and micronaire reading (Mike) and maturity ratio (MR). The studied cotton varieties include long staple cotton varieties i.e., Giza 86 and Giza 95 and extra-long staple cotton varieties i.e., Giza 92 and Giza 93, in terms of basic Egyptian cotton grade Good (G). The results of HVI and CCS measurements were detected by using descriptive statistics such as measures of central tendency and dispersion, skewness, and kurtosis. The CCS measurements were more stable than HVI measurements. Confidence intervals of CCS measurements were close to each other compared to HVI measurements. For instance, in Giza 92, confidence interval of UHM was 32.00-32.32for HVI and 32.50-32.55for CCS, adding to confidence intervals for FS were 45.19-46.83for HVI and 46.99-47.17 for CCS. Meanwhile, confidence intervals for Mike were 3.04–3.21 for HVI and 3.12–3.14 for CCS. Basically, sample sizes of CCS were larger more than sample sizes of HVI so that results of CCS measurements were more homogenous than HVI measurements. Applying reliability analysis for consistent results in CCS and HVI measurements elaborated Cronbach's value were more efficient than using Cronbach's value if item deleted for both CCS and HVI. Cronbach's value of CCS measurements was more than HVI measurements and that due to the homogeneity of CCS samples compared to HVI samples.

scholarly journals The Impact of Historical Gin Stand Technologies on Cotton Fiber and Seed Quality

2019 ◽  
Vol 35 (5) ◽  
pp. 775-785
Author(s):  
Derek P. Whitelock ◽  
Michael D. Buser ◽  
Carlos B. Armijo ◽  
S. Ed Hughs
Keyword(s):  
Seed Quality ◽  
Fiber Quality ◽  
Short Fiber ◽  
Fiber Content ◽  
Seed Damage ◽  
Study Results ◽  
The 1960S ◽  
Design And Manufacture ◽  
The Impact ◽  
Lower Capacity

Abstract. The trend in modern gin stand designs to increase gin stand production rate in terms of bales/h was generally achieved by increased width, narrower saw spacing, and higher saw loading. This study examined fiber length reductions, short fiber content, fiber neps, and cottonseed damage associated with five saw gin stands of differing production rates, design, and manufacture that represent a range of gin technologies developed since the 1960s to identify technologies from those earlier designs that may guide future gin stand research. Based on rated ginning rate, the gin stands were classified in two general categories, lower capacity (LC, 5 bales/h and less) and higher capacity (HC, 7.5 bales/h and higher). Fiber from the LC gin stands contained fewer fiber neps, longer fibers, less short fiber, and less foreign matter than fiber from the HC gin stands. In addition, cottonseed from the gin stand with lowest capacity had the highest residual linters content and the lowest overall seed damage which aligned with the short fiber content data. Both the LC gin stands were older models and had wider saw spacing; the oldest of them was substantially different from the other designs with two saw mandrels pulling fiber from the same seed roll position. Study results indicate that there may be historical gin stand technologies and relationships between gin parameters such as ginning rate per saw, saw spacing, and seed roll density, and fiber and seed quality that need to be further investigated. Keywords: Cottonseed quality, Cotton ginning, Fiber quality, Gin stand, Length, Neps, Short fiber content, Upland cotton.

scholarly journals KEMAJUAN GENETDX PADA DUA VARIETAS BARU KAPAS, KANESIA 8 DAN KANESIA

2020 ◽  
Vol 10 (2) ◽  
pp. 66
Author(s):  
. HASNAM ◽  
EMY SULISTYOWATI ◽  
SIWI SUMARTINI ◽  
FITRINTNGDYAH TRI KADARWATI ◽  
PRIMA D. RIAJAYA
Keyword(s):  
Gossypium Hirsutum ◽  
Competitive Ability ◽  
Fiber Strength ◽  
Fiber Quality ◽  
Insect Pest ◽  
Leaf Damage ◽  
High Yield ◽  
Good Tolerance ◽  
Breeding Lines ◽  
South Sulawesi

<p>Tujuan utama pemuliaan kapas di Indonesia adalah meningkatkan produktivitas dan kualitas serat dalam upaya meningkatkan pendapatan petani dan memperbaiki mutu benang tcnun seta kualitas tekstil yang harus bersaing di pasar internasional. Scjumlah enam persilangan telah dilakukan antara dua varietas dai India. I.RA 5166 dan SRT-1 dengan dua varietas dai Amerika Serikat, Dcltapine 55 dan Deltapinc Acala 90 dan satu vaietas dai Australia, Siokra. Seleksi individu, seleksi galur dan seleksi individu dalam galur dilaksanakan pada generasi F2 sampai F5 berdasarkan jumlah buah, tingkat kerusakan daun terhadap Sundapteryx biguttula. dan mutu serat; semua proses di atas dilakukan pada kondisi lahan tadah hujan, dan tanpa penggunaan insektisida terhadap tanaman; dari proses di atas diperoleh 12 galur harapan. Sejumlah 13 percobaan dilakukan antara tahun 1993 sampai dengan 2001 untuk mengamati kcragaan galur-galur baru tersebut; pengujian dilakukan di Jawa Timur dan Sulawesi Selatan, menggunakan teknik-teknik penelitian standar. Dengan proscdur ini dapat diidcntifikasi beberapa galur yang menunjuk¬ kan perbaikan serenlak hasil dan kualitas serat kapas. Beberapa penelitian juga dilakukan untuk mcngcvaluasi tanggap galur-galur tersebut pada tumpangsari dengan kedelai dan kacang hijau di Jawa Timur. Dua galur, 88003/16/2 dan 92016/6 (sudah dilepas dengan nama vaietas Kanesia 8 dan Kanesia 9 pada bulan Juni 2003), menunjukkan produktivitas dan kualitas serai yang lebih linggi. Rata-rata, kedua vaietas menghasilkan 1.85 ton dan 191 ton kapas berbiji per hektar atau 8-12% lebih tinggi dai hasil vaietas Kanesia 7 yang sudah dilepas sebelumnya. Persentase serat 35.2%, kekuatan serat berkisar antara 22.6-24.7 gram tex'1, serat lebih panjang dan berkisar 29.2-30.3 mm sedangkan angka mikroncr lebih rendah yang menyatakan bahwa serat lebih halus. Semua perbaikan di atas menunjukkan perbaikan mutu serat. Kanesia 8 dan Kanesia 9 juga menunjukkan peningkatan ketahanan terhadap Sundapteryx biguttula dan komplcks hama kapas. Kanesia 8 dan Kanesia 9 kurang kompctitif dalam tumpang sari dengan kedelai jika dibandingkan dengan Kanesia 7. Pada tumpang sari dengan kacang hijau Kanesia 8 juga mengalami kehilangan hasil yang tinggi, sedangkan Kanesia 9 menunjukkan toleransi yang tinggi dalam kompctisi dengan kacang hijau. Pelepasan Kanesia 8 dan Kanesia 9 akan memberikan pilihan varietas yang lebih banyak bagi petani dan perusahaan pemintalan untuk menyesuaikan dengan produk akhirnya.</p><p>Kata kunci : Gossypium hirsutum, prosedur pemuliaan, produktivitas, kualitas serat, Sundapteryx biguttula, tumpangsari</p><p> </p><p><strong>ABSTRACT </strong></p><p><strong>Genetic improvement on two new cotton varieties, Kanesia 8 and Kanesia 9</strong></p><p>The main objective of cotton breeding in Indonesia is to improve productivity and fiber quality which is aimed to increase farmers' income and to make beter yam and textile quality that has to compete in international market Six crosses were made between two Indian varieties, LRA 5166 and SRT-1 with two USA vaieties, Deltapine 55 and Deltapinc Acala 90 and one Australian variety, Siokra. Individual plants, lines and individual within lines were selected on F2-F5 generations based on boll- counts, leaf-damage by jassids and fiber traits, those were conducted under rainfed and insecticide-ree condition; twelve promising lines were produced from this process. A total of 13 trials were carried out to observe performance of these new lines during 1993 to 2001; those were located in East Java and South Sulawesi using the standardized experimental techniques. By these procedures make it possible to identify several breeding lines showing simultaneous improvement in yield and fiber quality. Several tests were also made to evaluate response of those lines under intercropping with soybean and mungbean, which were located in East Java. Two breeding lines, 88003/16/2 and 92016/6 (those have been released as Kanesia 8 and Kanesia 9 in 2003), showed higher productivity and fiber quality. In average, these new vaieties produced 1.85 and 1.91 ton ha'1 seed cotton respectively or 8 to 12% higher than those on Kanesia 7, the previously released vaiety. Lint turn-out was 35.2% fiber-strength was varied from 22.6 to 24.7 gram tex'1 , fiber lengths ranged from 29.2 to 30.3 mm with lower micronaire-valucs indicating better fiber-ineness. All of those improvements represented a trend toward a higher quality iber. Kanesia 8 and Kanesia 9 also showed a slight improvement in resistance to jasssids and insect pest-complex. Kanesia 8 and Kanesia 9 performed lower competitive ability under intercropping with soybean in comparison with Kanesia 7. Under intercropping with mungbean Kanesia 8 also suffered high yield loss, wherein Kanesia 9 showed good tolerance to mungbean. The release of Kanesia 8 and Kanesia 9 is expected to give a broader choice for the cotton growers and spinning-mills to match with their inal product.</p><p>Key words: Coton (Gossypium hirsutum), breeding procedure, productivity, liber quality, Sundapteryx bigullul. inter¬ cropping.</p>

scholarly journals Phenotypic adaptability of cotton genotypes to the brazilian cerrado for yield and fiber quality

2020 ◽  
Vol 36 (4) ◽  
Author(s):  
Mayara Fávero Cotrim ◽  
Francisco José Correa Farias ◽  
Luiz Paulo de Carvalho ◽  
Larissa Pereira Ribeiro Teodoro ◽  
Carlos Antonio da Silva Junior ◽  
...  
Keyword(s):  
Fiber Length ◽  
Fiber Strength ◽  
Fiber Quality ◽  
Block Design ◽  
Brazilian Cerrado ◽  
Gxe Interaction ◽  
Randomized Block Design ◽  
Cotton Genotypes ◽  
High Predictability ◽  
Fiber Traits

Studies on the adaptability and stability are fundamental for plant breeding as they are an alternative to reduce the effects of genotypes x environments interaction (GxE). Moreover, they help identify cultivars with predictable behavior, which are responsive to environmental improvements, subsidizing cultivar recommendation. This study aimed to investigate the genotypes x environments interaction in cotton genotypes grown in the Brazilian Cerrado and identify genotypes for favorable and unfavorable environments. During the 2013/2014 and 2014/2015 seasons, 19 competition trials were carried out with cotton in a randomized block design, with 12 treatments, and four replications. The traits cotton seed yield, fiber percentage, fiber length, and fiber strength were evaluated. Results revealed significant GxE interaction for all the fiber traits evaluated. Genotype BRS 369 RF revealed general adaptability and high predictability for the fiber traits evaluated.

scholarly journals Reaction of Select Peanut (Arachis hypogaea L.) Lines to Southern Stem Rot and Pythium Pod Rot Under Varied Disease Pressure

1989 ◽  
Vol 16 (1) ◽  
pp. 9-14 ◽  
Author(s):  
O. D. Smith ◽  
T. E. Boswell ◽  
W. J. Grichar ◽  
C. E. Simpson
Keyword(s):  
Arachis Hypogaea ◽  
Disease Incidence ◽  
Sclerotium Rolfsii ◽  
Stem Rot ◽  
Resistant Parent ◽  
Breeding Lines ◽  
Arachis Hypogaea L ◽  
Significant Yield ◽  
Considerable Resistance ◽  
Disease Pressure

Abstract Eight breeding lines, three parents, and the cultivar Florunner were compared under two levels of disease pressure induced by Sclerotium rolfsii Sacc., or Pythium myriotylum Drechs. at each of two locations for three years to ascertain the effectiveness of the host plant resistance to each pathogen. Varied disease pressures were created by application of fungicides and supplement of fungal inoculum. Mean Florunner pod yields varied more than 1000 kg/ha as a result of the S. rolfsii treatments but the yields of the resistant TxAG-3 were not affected. Disease incidence, as measured by frequency of S. rolfsii infection sites and diseased pods, was much higher for Florunner than TxAG-3. Breeding lines for which TxAG-3 was a parent sustained significant yield reductions. The disease incidence in these lines was higher than the resistant parent, equal or less than Tamnut 74, their other parent, and less than Florunner. The grades of TxAG-3 and its derivatives were lower than Florunner. Pod rot incidence differed for the P. myriotylum treatments but pod yields were not different. TxAG-3 and Toalson sustained less pod disease than Florunner and Tamnut 74. The percent of diseased pod tissue for one derivative of Toalson was lower than Toalson and TxAG-3, and that of one TxAG-3 derivative was equal to its best parent. The breeding lines varied in reaction to the two diseases and some lines showed considerable resistance to both organisms.

Sign in / Sign up

Export Citation Format

Share Document