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991.
Cracking of seed coats in soybean (Glycine max (L.) Merr.) deteriorates the external appearance of seeds and reduces their commercial value. Two types of cracking have
been reported that occur in some cultivars: Type I with irregular cracks and Type II with net-like cracks. This study was
conducted to determine the genetic basis of net-like cracking. Genetic analysis was performed using F1 plants produced by crossing Uzuramame, a Japanese landrace with black seed coats having net-like cracking and a Clark mutant
with black seed coats, their F2 population and F3 lines. Degree of cracking in individual plants was calculated by averaging cracking index (no cracking: 0 to severe cracking:
4) of total or 100-seed samples (average cracking index, ACI). Uzuramame exhibited intense cracking, whereas the Clark mutant
showed slight cracking. Intermediate degree of cracking in F1 plants suggested incomplete dominance. ACI of F2 plants was continuously distributed. Gene number involved was estimated to be 1.4 by Wright's method. All F3 lines derived from F2 plants with ACI more than 2.8 displayed severe cracking phenotypes. In contrast, F3 lines derived from F2 plants with ACI less than 2.8 segregated from low to high ACI (0.5 to 3.2). When F2 plants were classified as slight (ACI<2.8) or severe (ACI>2.8) cracking, the frequency distribution of the F2 plants fitted to a 3:1 ratio. Genotypes of SSR marker Satt264 that is closely linked to SoyPRP1 locus for proline-rich cell
wall protein had a minor effect on ACI. Further, seed weight was positively associated with ACI (r =0.46**). Our results suggest that net-like cracking is controlled primarily by a major gene, and SoyPRP1 and gene(s) contributing
to seed weight may have minor effects on the intensity of cracking.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
993.
通过网箱养殖尼罗罗非鱼、鲤鱼的试验,总结了高产网箱养鱼的条件、方法及主要技术措施等实跨经验,分析了试验取得的成果,为今后的规模生产及如何提高网箱养鱼的产量提供了科学依据。 相似文献
994.
Kyotaro Noguchi Tadashi Ishii Toshiro Matsunaga Koichi Kakegawa Hiroaki Hayashi Toru Fujiwara 《植物养料与土壤学杂志》2003,166(2):175-178
We examined concentrations of boron (B) and dimerization of rhamnogalacturonan II (RG‐II), a B‐binding polysaccharide, in the cell wall of a low‐B sensitive mutant of Arabidopsis thaliana, bor1‐1, to investigate possible effects of the bor1‐1 mutation on the biochemical form of pectins in the cell wall. In the bor1‐1 mutant, B concentrations in the cell wall from shoots were lower than those in the wild type at low B supply, whereas they were similar at sufficient B supply. The amount of B present as borate ester of the RG‐II dimer (dRG‐II‐B) in the bor1‐1 mutant was lower than that in the wild type at low B supply. In the wild type, about 90 % of RG‐II was present as dRG‐II‐B, both, at low and sufficient B supply. In the bor1‐1 mutant, about 60 % of RG‐II was in its monomeric form (mRG‐II) at low B supply, whereas more than 85 % of it was present as dRG‐II‐B at sufficient B supply. However, similar as the wild type, mRG‐II derived from the bor1‐1 mutant was able to form dRG‐II‐B in vitro in the presence of borate and lead. Sugar composition of cell wall fractions was similar in both genotypes. These results suggest that the polysaccharide composition in the cell wall was not strongly affected by the bor1‐1 mutation. The observed difference in dimerization of RG‐II at low B supply is most likely due to a reduced B concentration in the shoots of the bor1‐1 mutant. 相似文献
995.
Nguyen Tran Nguyen Mark J. Dudzinski Pravat K. Mohapatra Kounosuke Fujita 《Soil Science and Plant Nutrition》2005,51(5):737-740
Distribution of aluminum (Al) within plant components and Al-induced changes in cell wall polysaccharides in root tips of Eucalyptus camaldulensis Dehnh. seedlings were compared with those of Melaleuca cajuputi Powell. In E. camaldulensis , 0.5 mM Al (pH 4.2 for 40 d) reduced plant dry weight by 50%, increased callose concentration in the root tips and induced leaf necrosis. In comparison with M. cajuputi , Al concentrations were higher in roots and leaves of E. camaldulensis on both a fresh weight basis and in the cell sap, but were lower in the cell wall. Al increased pectin, hemicellulose and cellulose concentration in the cell walls of E. camaldulensis root tips. Al-induced leaf necrosis and growth reduction in E. camaldulensis is discussed in the context of potentially toxic concentrations of Al in plant tissue and changes in polysaccharide content which could reduce water and nutrient uptake and cell wall extensibility in roots. 相似文献
996.
在一些水利工程如泵站、水闸等的施工实践中,常常会碰到在软基上进行深基开挖所带来的问题,尤其对受场地限制的工程来说,无法进行常规开挖,而必须考虑其它的开挖措施。通过经济技术比较及实践,证明了利用沉管灌注桩围壁进行深基开挖的优越性,并且通过对整个施工过程的观测、试验、总结,为这一技术的进一步应用提供了实践经验。 相似文献
997.
Tank irrigation is one of the oldestsources of irrigation in India. Decline inthe area irrigated over the years due toinadequate operation and maintenance,large-scale development of groundwatersources, disintegration of traditionalirrigation institutions, heavy siltation,encroachment, etc., has resulted in heavysupplemental well irrigation in order toavoid crop losses. Rice yield from farmswith supplemental well irrigation wasobserved to be high. Even though it ispossible to calculate the value ofgroundwater for different years, it isdifficult to obtain the value of thegroundwater used to stabilize riceproduction from tank irrigation. The modeldeveloped in this paper is used tocalculate the stabilization value ofgroundwater using the Srivilliputhur BigTank, which is a representative tank inTamilnadu, India.A mathematical formula is used to model theeconomics of conjunctive surface andgroundwater irrigation systems. Analyticalexpressions for the value of groundwaterand the stabilization value of groundwaterare derived, assuming that the amount ofsurface water is a general stochasticvariable with a probability densityfunction, and that the demand function forirrigation water is also of that generalform. Finally, the model is applied toreal data collected during the period 1986to 2000 for the Srivilliputhur Big Tank inTamilnadu, India, and the value ofgroundwater and the stabilization value ofgroundwater are calculated at 1999–2000constant prices. The results indicatedthat the stabilization value of groundwater(covering the entire tank area of 402 ha.)was Rs. 166,677, while the value ofgroundwater was Rs. 1,064,720. Thus, about15.7% of the value of the groundwater wasused for its stabilization. Using thestabilization value of the groundwater infuture investment analysis will help tomore accurately indicate project benefitsdue to groundwater supplementation in thetank command areas. 相似文献
998.
针对以往推广的沼气池存在着滞留期长、原料转换率低,产气率不高,易结壳,换料困难等缺陷,结合贵州农村实际,围绕“一池三改”的要求,积极探索新池型。详细介绍了自主研发的多能高效A型沼气池结构特点及施工的关键技术。 相似文献
999.
Firmness is a major quality attribute of fresh cherries, and is also a main factor affecting susceptibility to bruising and postharvest rots. In order to identify the factors determining the textural differences between genotypes, we evaluated the solubilization, depolymerization and monosaccharide composition of pectin and hemicelluloses from two cultivars with contrasting firmness (‘Sweetheart’, firm and ‘Newstar’, soft) at four different developmental stages. Firm ‘Sweetheart’ cherries had higher contents of cell wall material than soft ‘Newstar’ fruit. Moderate depolymerization of hemicellulose and tightly bound pectins was detected irrespective of cultivar firmness. The general pattern and extent of uronic acid solubilization was quite similar in both cultivars. Rhamnogalacturonan I (RG-I) seemed to be preferentially solubilized in firm ‘Sweetheart’ fruit as opposed to tightly bound homogalacturonans (HG) in soft cherries. Pectic polymers with higher neutral sugar to uronic acids ratio were found from early development in soft ‘Newstar’ fruit. Overall, soft ‘Newstar’ fruit had reduced wall content and higher branching of tightly bound pectins than firm ‘Sweetheart’ fruit. These factors may be associated with the varietal differences in cherry firmness. 相似文献
1000.
分析了目前航煤储罐内防腐涂料的使用状况,列举了国内外航煤储罐内防腐涂料的使用标准和应用实例,指出民航新建航煤储罐内防腐采用不导静电涂料不会构成静电危害,并提出了民航新建航煤储罐内防腐涂料的选用建议和安全防范措施。 相似文献