ที่มา:วิทยาสารเกษตรศาสตร์ สาขา วิทยาศาสตร์

หัวเรื่อง:ประสิทธิภาพในการตรึงไนโตรเจนของไรโซเบียมในโสนอินเดียและโสนอาฟริกันจากดินภาคต่างๆ ของประเทศไทย

ผู้เขียน:นายนันทกร บุญเกิด, อาจารย์, Suwannee Promsiri

สื่อสิ่งพิมพ์:pdf

Abstract

Sesbania speciosa and Sesbania rostrata are high potential symbiotic N-fixing legumes to be used as green manuring for both field crops and rice. Due to both Sesbania species are introduced crops thus we hypoth?esised that the suitable effective strains for these two Sesbania species may not present in Thai soil the objective of this study was to determine the effective strains of rhizobia for the two Sesbania species from soils in differ?ent part of Thailand. It was found that Sesbania speciosa rhizobia were different in terms of strains, population density and effectiveness in different locations. Most soils contained very low to moderately effective strains of rhizobia. For Sesbania rostrata, variation in rhizobial strains was not great most soil contained moderately effec?tive strains. However from the study we found some high effective strains of rhizobia for both Sesbania species were isolated. Therefore, to be most benefitial from using both Sesbania as green manuring the plants should be inoculated with their effective rhizobial strains isolated from this study for every new introducing areas.

Article Info

Agriculture and Natural Resources -- formerly Kasetsart Journal (Natural Science), Volume 027, Issue 3, Jul 93 - Sep 93, Page 292 - 302 |  PDF |  Page

ที่มา:วิทยาสารเกษตรศาสตร์ สาขา วิทยาศาสตร์

หัวเรื่อง:การใช้เทคนิคทางด้านนิวเคลียร์และวิธีการอื่นๆ เพื่อการคัดเลือกถั่วเขียวและเชื้อไรโซเบียมเพื่อการตรึงไนโตรเจนและเพิ่มผลผลิตถั่วเขียว

ผู้เขียน:นายนันทกร บุญเกิด, อาจารย์, Precha Wadisirisuk, Achara Nantakit, Setha Siripin, Toshifumi Murakami

สื่อสิ่งพิมพ์:pdf

Abstract

Mungbean (Vigna radiata) is a nitrogen fixing crop. To be most useful to farmers the recommended mungbean should obtain nitrogen from atmosphere through symbiotic fixation with rhizobia. The objective of this study was to select mungbean lines and rhizobial strains for high nitrogen fixation. Results obtained from screening of 423 mungbean lines indicated that there were variation in nitrogen fixation, nodulation nitrogenase activity and growth of mungbean lines. The mungbean lines VA 1948, VC 1776, VC 3128, VC 1830, VC 1693 and VC 2335 were higher in nitrogen fixation than the recommended cultivars. Using 15N natural abundance technique to quantify the amount of nitrogen fixed found that mungbean line fixed nitrogen ranging from 0-300 mg N per plant for 35 days. It was interesting to find that the hybrid line F7 of VC 2768 A/1560 D which was the highest fixing line could fix N up to 19.2 kg per rai, resulted in the farmer could get more profit of 235-300 baht when using this line. In estimating seasonal fixing of nitrogen, it was found that mungbean start fixing N in small amount at early stage and gradually increased until reach maximum at pod filling stage or about 41?45 days and the N fixed was gradually declined until stop fixing at maturity. Investigating of rhizobial strains infecting mungbean cultivars revealed that some strains were specific to a mungbean cultivar. However most mungbean rhizobia were effective. There were high correlation among nodule number, nodule mass, ARA and plant biomass. To quantify nitrogen fixation in mungbean under field condition it is necessary to find a suitable reference or non fixing crop. It was found that sorghum was the most suitable reference plant for measuring N2 fixation in mungbean. Under normal field condition the selected mungbean line could fix N upto 70%.

Article Info

Agriculture and Natural Resources -- formerly Kasetsart Journal (Natural Science), Volume 027, Issue 2, Apr 93 - Jun 93, Page 162 - 176 |  PDF |  Page