ที่มา:วิทยาสารเกษตรศาสตร์ สาขา วิทยาศาสตร์

หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Field Trial and Agronomic Performance Naturally-Colored Cotton: Antibiosis and Leaf Damaging Tests Against Key Insect Pests, )

ผู้เขียน:ดร.ประภารัจ หอมจันทน์, ศาสตราจารย์, นางอรุณี วงศ์ปิยะสถิตย์, ศาสตราจารย์

สื่อสิ่งพิมพ์:pdf

Abstract

Laboratory tests were conducted to acquire the antibiotic effect of white and naturally-colored cotton varieties/lines, AP2, PM1 and PM4 compared to the control, SR60, using fresh leaves fed to the 3rd instar Helicoverpa armigera larvae. There were no significant differences found in the developmental times and weights of the bollworm larvae and pupae fed on the leaves of the different cotton varieties/ lines except for the percentage of adult abnormalities in PM1and PM4. The leaf damage by the leafhoppers was undertaken in a greenhouse using adult and nymph leafhoppers released in a screen cage containing one month-old cotton plants of each variety/line grown in pots. After 14 days, the results revealed that AP2 had the lowest score for hopperburn rating (3.5). Cotton variety trials in sprayed and unsprayed plots were conducted during 2006 and 2007 at two locations, the Field Crop Research Center at Nakhon Ratchasima and a farmer’s field at Thongpapoom, Kanchanaburi. The mean annual number of key pests and the annual yield of each variety/line at each location were compared and the average agronomic performance of each variety/ line was HVI analyzed. At Nakhon Ratchasima, leafhoppers were more abundant than aphids and whiteflies in both 2006 and 2007. There was a significant difference in the mean leafhopper numbers for AP2 and PM4 between both plots during the two years, while for PM1 there was a significant difference in 2007 only. Seed weights of SR60 and PM1 differed between the sprayed and unsprayed plots in 2006. At Tongpapoom, Kanchanaburi, both SR60 and PM4 in 2006, and PM4 again in 2007 had significantly different amounts of leafhopper between the sprayed and unsprayed plots. The yield of SR60 in the sprayed plot significantly differed from the unsprayed plots in 2006. Agronomic performance of each cotton fiber found only micronaire range in PM1 from Thongpapoom and the fiber lengths of SR60, AP2 and PM1 grown at Nakhon Ratchasima to be designated as premium. At Tongpapoom, the AP2 fiber length fell in the base range. The percent lint of AP2 was the highest at Nakhon Ratchasima, while PM4 had the lowest value for this parameter at both locations.

Article Info

Agriculture and Natural Resources -- formerly Kasetsart Journal (Natural Science), Volume 042, Issue 4, Oct 08 - Dec 08, Page 589 - 598 |  PDF |  Page

ที่มา:วิทยาสารเกษตรศาสตร์ สาขา วิทยาศาสตร์

หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : A Field Trial on the Efficacy of Ivermectin, Albendazole and Coumaphos Against Parasites of Buffaloes)

ผู้เขียน:Wichai Suphalucksana, F.A. Ching

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Abstract

Results from identification work yielded six nematodes, one cestode and one trematode, as the helminths accounting for the severe, mixed worm infection in the ranch. The Egg per Gram (E.P.G.) resulted to confirm the ovicidal effect of albendazole and Ivermectin against nematodes, however, the latter have more prolonged action than the former. Gross fecal examination showed that the mentioned drugs had a vermifugal and vermicidal effect on the nematodes. However, Ivermectin lacks this properties against cestodes. Insecticidal activity of Ivermectin was also compared with Coumaphos against lice (Haematopinus spp.). Both displayed the same activity with regards to the ability to get rid of the external parasites. Economic analysis showed that Ivermectin had more expensive than Albendazole and Coumaphos which combined regardless of labor and equipment needed. However, Ivermectin-treated animals showed a higher weight gain than those treated with Albendazole and Coumaphos and control.

Article Info

Agriculture and Natural Resources -- formerly Kasetsart Journal (Natural Science), Volume 025, Issue 2, Apr 91 - Jun 91, Page 256 - 260 |  PDF |  Page

ที่มา:วิทยาสารเกษตรศาสตร์ สาขา วิทยาศาสตร์

หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Performance of Periparturient Dairy Cows Fed Alfalfa Hay in Total Mixed Ration : A Field Trial in Thailand)

ผู้เขียน:ดร.ธีระ รักความสุข, รองศาสตราจารย์, Sunthorn Rungruang2,, ดร.อาภัสสรา ชูเทศะ, รองศาสตราจารย์, Theo Wensing

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Abstract

Performance of 20 periparturient Holstein Friesian dairy cows fed alfalfa hay-base total mixed rations during transition and lactation periods was studied in a commercial dairy farm. From 7 d prior to anticipated calving date until 7 d after calving, all cows were also drenched with 400 ml of propylene glycol once daily. Blood samples were collected at -2, 1, 2, 3 and 4 wk from parturition. Milk yields were recorded daily, and milk samples were collected twice a week to determine milk compositions. Compared with the concentrations at -2 wk, serum glucose and urea nitrogen concentrations decreased whereas serum non-esterified fatty acid and ?-hydroxybutyrate concentrations increased after calving. These results indicated that these cows entered some degrees of negative energy balance. Average milk production during 30 d postpartum was 34.8 ? 8.7 kg/d. Average days from calving to first service was 86 ? 24 d, and 55% of 20 cows were conceived at first service. In conclusion, cows fed alfalfa hay-base diet and drenched with propylene glycol during periparturient period could improve negative energy balance, milk yield and conception rate. However, replacing roughages from agro-industry by product with alfalfa hay in Thai dairy farms would depend on the economical analysis because most alfalfa hay was imported from foreign country.

Article Info

Agriculture and Natural Resources -- formerly Kasetsart Journal (Natural Science), Volume 042, Issue 1, Jan 08 - Mar 08, Page 11 - 18 |  PDF |  Page