 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Feasibility Study on Insect Pests Affecting the Growing of Naturally Colored Cotton Comparing with White Cotton in Thailand) ผู้เขียน: ดร.ประภารัจ หอมจันทน์, ศาสตราจารย์ , นางอรุณี วงศ์ปิยะสถิตย์, ศาสตราจารย์ ,  Somchai Piyapuntawanon สื่อสิ่งพิมพ์:pdf AbstractFeasibility study of growing naturally colored cotton, Gossypium hirsutum, PM1and PM4 and Gossypium arboreum, PM2 along with white cotton, G.arboreum, PM3 comparing with the standard white G.hirsutum, SR60 was conducted from 2003-2004 at the National Corn and Sorghum Research Center, Pak Chong, Nakhon Ratchasima. RCB was used with 4 replicates, each with 5 rows of each variety. Data of insects were biweekly collected in the three middle rows for four consecutive times. In both years, the kinds and mean numbers of key pest were mainly leafhopper, Amrasca biguttula, and the plant bug, Megacoelum biseratense while the bollworm, Helicoverpa armigera was found in 2004 only. The 2003 and 2004 similar results revealed that the leafhoppers on PM1 and SR60 and those on PM2 and PM3 were not significantly different while all were significantly different from PM4. The average amounts of plant bug on every variety in both years were also found not to be significantly different from one another. Comparing the numbers of leafhopper between 2003 and 2004, they were significantly different at all varieties except PM2, while those of the plant bug on every variety did not significantly differ. As for the fiber analysis and % gin turn out, PM1 was found to have the acceptable qualities compared with the standard ranges of fiber determination as well as the commercial variety, SR 60. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : New Mutant Cotton Lines of Good Yields and Resistance to Some Insects by ?-Irradiation) ผู้เขียน:ดร.ประภารัจ หอมจันทน์, ศาสตราจารย์, นางอรุณี วงศ์ปิยะสถิตย์, ศาสตราจารย์, Somchai Piyapuntawanon สื่อสิ่งพิมพ์:pdf AbstractM2 through M6 of the ?-Irradiated mutant lines, AP1 an dAP2 were tested for insect resistance and good yields comparing to the control varieties, SR2 and R1, in field and laboratory conditions. Field tests at Suwan Farm revealed seed weight , lint weight and % lint of AP1 to be the greatest while the highest weight of 10 fresh bolls was found in AP2. Fiber quality of all varieties/lines were found to be similar and were within the rather high standard levels. Visual rating of damage caused by H. armigera (square and damage) and A. biguttata (hopper burn) to the controls and mutants were similarly rated as moderately resistant and susceptible respectively. According to antibiotic test and chemical analysis of H. armigera, the small increased larval weight and the morphologically abnormal adult fed from leaves of AP1 and AP2 were believed to be partially caused by other chemical substances beside gossypol and flavonoids whose contents did not exceed the giver toxic level inhibiting growth. Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Observation of Gamma Irradiated Cotton Populations on Trend of Cotton Leafhopper Resistance Using Hopperburn Index) ผู้เขียน:ดร.ประภารัจ หอมจันทน์, ศาสตราจารย์, นางอรุณี วงศ์ปิยะสถิตย์, ศาสตราจารย์, Somchai Piyapuntawanon สื่อสิ่งพิมพ์:pdf AbstractThe experiments were conducted during the 2000 and 2001 cotton growing seasons at Suwan Farm, Pakchong, Nakon Ratchasima to investigate the damage of gamma irradiated cotton populations caused by the cotton leafhopper Amrasca bigutulla bigutulla using hopperburn index. Preliminary observation on M1 populations of cotton varieties, SR2, R1, AP1 and AP2, was administered in the year 2000. After which the M2 seeds of SR2, R1, AP1 and AP2 from the first year were used in the second year test in RCB design with 4 replicates. The numbers of cotton jassid from 2 leaves, one from the top and the other from the middle portions of the canopy from 10 plants in 3 middle rows of each tested variety were recorded on Days 45, 60 and 75 after germination. Visual rating on leafhopper damage was employed and hopperburn index was calculated. It was found that on Day 45, M2 populations of every tested line expressed moderate resistance to the leafhopper except R1 susceptible as indicated by hopperburn indices. As the plants grew older to Days 60 and 75 the resistance reduced. The hopperburn indices were of negative correlation to the leafhopper whose amounts were high on Day 45 and decreased and rose again on Days 60 and 75, respectively. Scanning Electron Microscope (SEM) also showed AP2 and R1 with the greatest and lowest hair densities on Day 45 resulting in low and high hopperburn indices, respectively. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Integration of Resistant Mutants with Neem Extract in Cotton Insect Control) ผู้เขียน:P. Hormchan, A. Wongpiyasatid, S. Piyapuntawanon สื่อสิ่งพิมพ์:pdf AbstractThe studies at Suwan Farm during 1997-98 and 1998-99 were set up to show exp.2 with the application of neem extract integrated with cotton resistant variety lines as the insect control method to give better yields than those obtained in exp.1 using resistant plant as principal control alone. AP1 and AP2, the mutant lines possessing antibiosis mechanism against some major insect pests of cotton and SR60, the recommended variety were used in the test. It was found that the average amount of jassids on the mutants and SR60 in exp.1 did not significantly differ from those in exp.2 while there are significant differences between the numbers of bollworm and cotton plant bug on each variety/line of both tests. The comparison of average seed yields also revealed highly significant increase of seed weight in AP1 and AP2 in exp.2 whereas the increase in SR60 was not that high. Concerning fiber quality parameters, fiber length of all variety/line in both experiments were in medium group with their uniformities and micronaires to be very high and desirable respectively. |