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991.
992.
氮营养水平对秋马铃薯块茎发育中淀粉合成关键酶的影响 总被引:3,自引:0,他引:3
【目的】研究在秋季栽植条件下不同氮营养水平对马铃薯块茎发育过程中淀粉合成关键酶的影响。【方法】以高、低两类淀粉型品种为试验材料,4种氮营养水平处理,块茎形成后每隔7d取样测定块茎发育过程中的ADPG焦磷酸化酶(ADPGPPase)、可溶性淀粉合成酶(SSS)、淀粉分支酶(SBE)和结合性淀粉合成酶(GBSS),探讨他们之间的内在联系。【结果】结果表明:随着生育期的推进,各马铃薯块茎中不同施氮水平下的ADPGPPase、SSS、GBSS、SBE,呈现先逐渐增加,达到最大值后又开始下降的单峰曲线变化趋势,各施氮水平组的淀粉合成酶活性均在出苗后54~61d左右达到最大值。随着施氮量的增加,ADPGPPase、SSS也出现先升后降的单峰曲线变化趋势,而对于GBSS和SBE的影响,品种间表现差异。低淀粉品种CY-117的ADPGPPase、SSS的含量在各施氮水平下均高于高淀粉品种QS-2,具有较高的ADPGPPase、SSS活性。在氮营养影响条件下,SSS活性与淀粉总含量和支链淀粉的含量极显著正相关(r总淀粉=0.86**,r支链淀粉=0.83**),而与直链淀粉含量相关不大。【结论】氮营养主要是通过影响SSS的活性来实现对马铃薯块茎淀粉含量的影响。 相似文献
993.
研究了密度和分蘖对超甜玉米‘晶甜8号’产量和农艺性状的影响,结果表明:‘晶甜8号'产量随种植密度的增加而增加,种植密度为7.5万株/hm2时产量最高.穗长、鲜果穗重和分蘖数随密度的增加而降低;株高、穗位高、秃尖长随密度增加而增加.适当增加种植密度可使‘晶甜8号’采收期提前,生育期缩短,但与分蘖去除与否无关.同一种植密度下保留分蘖导致鲜果穗重和产量下降、株高和穗位高增加、穗长和秃尖长变短,但差异不显著.‘晶甜8号’的适宜种植密度应在6.0万株/hm2左右,生产上不必去除分蘖. 相似文献
994.
[目的]为建立3种毛色貉生物学特性数据库提供理论依据。[方法]以红褐色乌苏里貉、野生乌苏里貉和吉林白貉为研究对象,利用外周血淋巴细胞培养法制备染色体标本,对3种毛色乌苏里貉的染色体数目进行比较。[结果]红褐色乌苏里貉和野生乌苏里貉二倍体细胞染色体数为56的细胞频率分别为86%和83%,表明红褐色乌苏里貉和野生乌苏里貉种群体细胞的染色体众数为56。吉林白貉二倍体细胞的染色体数目为56的细胞频率为70%,低于其他2种貉。[结论]红褐色乌苏里貉和野生乌苏里貉的染色体众数相同,均为56;吉林白貉的染色体众数为56或57,其染色体数目存在多态现象。 相似文献
995.
《Plant Production Science》2013,16(1):56-61
AbstractThe number of grains per spikelet and the number of spikelets per spike are important factors that influence grain yield in wheat. Three wheat genotypes in four foreign groups (OA, OC, OH and OJ) differing in spike type and Japanese cultivars (cvs) were grown under various combinations of seeding densities and fertilization levels. In all groups, the spikelet number per spike and the spike length at maturity were highest at low seeding densities and high levels of fertilization. The OA group (Nepal) and Haruyutaka (Japanese cv) gave a weak response in spikelet number per spike, while the OJ group (Xinjiang Uygur, China) gave a weak response in spike length. The OC group (except for T6), the OH group (Tibet) and Japanese cvs (except for Haruyutaka) responded to treatments in both spikelet number per spike and spike length. The T6 genotype in the OC group (Nepal) gave a weak response in both spikelet number per spike and spike length. Although the OA group had the longest spikes and the OJ group had the shortest spikes, there was no difference in the duration of spike elongation between the OA group and the OJ group. Spike length appeared to be determined mainly by the rate of spike elongation and was not restricted by the dry weight of the spike during the growth phase of the spike. 相似文献
996.
《Plant Production Science》2013,16(4):299-306
AbstractIn sweet sorghum, which is a potential biomass crop, the diameter of internode is an important component of stem yield. However, the thickening of successive internodes is poorly understood. The objective of this study was to clarify the relationship between the thickening of successive internodes using the age indicated by the leaf number on the main stem (AL) as a time scale. Furthermore, the relationship between the elongating and thickening period of successive internodes along the stem was analyzed. Internodes were collected from AL3, when the 3rd leaf had just expanded above the 2nd leaf sheath, to AL17, and at 9 weeks after heading as final harvest. Although the internode thickening patterns based on AL could not be combined into one or a few patterns, a significant correlation (P<0.001) was found between internode position and AL at which the internodes were thickening, suggesting that a regularity of internode thickening existed among successive internodes. The higher the internode position, the longer the first half of the thickening period (from 15% to 50% of thickening), whereas the period of the second half (50%–85% thickening) was constant irrespective of internode position. These results suggest that the degree of the elongation and thickening of successive internodes can be estimated by using AL. 相似文献
997.
Nan Su San Masahiro Yamashita Shunsuke Adachi Takanari Tanabata Taiichiro Ookawa 《Plant Production Science》2013,16(4):302-310
ABSTRACTLeaf erectness is an important agronomic trait for improving canopy photosynthesis in rice. It is well known that leaf inclination angle (LIA) decreases after expansion during ripening. However, the high-yielding indica cultivar ‘Takanari’ retains a greater LIA during ripening than the high-quality japonica cultivar ‘Koshihikari’. To clarify the cause of the cultivar difference in LIA, we investigated anatomical characteristics of the lamina joint of a flag leaf. We found a close linear correlation between LIA at the centre and at the base of the leaf blade in both cultivars during ripening. The length of the lamina joint increased significantly more on the adaxial side of a leaf (the margin of the collar) than on the abaxial side (the abaxial side of the central part of the collar) in ‘Koshihikari’ after leaf expansion, but there was no clear difference in ‘Takanari’. We found a close linear correlation between the ratio of lamina joint length on the adaxial to abaxial sides and LIA in ‘Koshihikari’ and ‘Takanari’ during ripening. In ‘Koshihikari’, the average length of cells on the adaxial side increased significantly after leaf expansion, with no significant increase in that on the abaxial side and no significant change in cell number on either side. In ‘Takanari’, cell length and cell number showed no significant changes on either side of the lamina joint. We conclude that the cultivar difference in LIA during ripening is caused mainly by cell elongation on the adaxial side of the lamina joint.List of Abbreviations: k: light extinction coefficient; LIA: leaf inclination angle; QTL: quantitative trait locus 相似文献
998.
《Journal of Crop Improvement》2013,27(1-2):531-558
SUMMARY Yams (Dioscorea spp.) constitute an important starchy staple in sub-Saharan Africa (SSA) where food security for a growing population is a critical issue. Mixed cropping in yam based systems is the norm in the region and productivity of yams in these systems is below potential. It is concluded that there is much scope for improvement of yam based cropping systems in SSA in order to meet the needs of the region. The strategy of crop breeding to select yam varieties suitable for various cropping systems must consider a truly multidisciplinary systems approach. Further manipulation must be made to tuber dormancy to expand flexibility in field propagation in different cropping systems and improve storage and marketing. The sustainability of yam based cropping systems in SSA could improve if agronomic research was focused on strategies for improving soil fertility, weed and pest management including design of cropping systems and suitable rotations. 相似文献
999.
《Journal of Crop Improvement》2013,27(1-2):91-111
SUMMARY Experiments, which have investigated the effect of elevated concentrations of atmospheric CO2 on the physiology, growth and yield of potato (Solanum tuberosum L.), are reviewed. These studies were conducted in controlled environment chambers, in glasshouses, in open top field chambers as well as using free air carbon dioxide (FACE) exposure systems. In general, photosynthesis is stimulated by elevated CO2 initially although long-term exposure leads to acclimation. The stomata of potato leaves partially close in response to elevated CO2 and starch granules build up in the chloroplasts. Although above- and below-ground biomass production is stimulated, accelerated senescence limits growth towards the end of the growing season exposure to elevated CO2 stimulates tuber yield, the magnitude of which depends on agronomic practise, cultivar choice and growing conditions. The beneficial effects of elevated CO2 may be reduced by interaction with other components of climate change, such as drought stress. Modelling of the effects of climate change on potato yield has predicted an increase in yields in northern Europe with little change in central and southern Europe. It is suggested that further research is needed to understand the reasons for photosynthetic acclimation, field trials are also needed to understand and quantify the interaction between elevated CO2 and drought stress. 相似文献
1000.
Kensuke Hirose Satoshi Mikawa Naohiko Okumura Go Noguchi Kazuo Fukawa Naoe Kanaya Ayumi Mikawa Aisaku Arakawa Tetsuya Ito Yoichi Hayashi Fumio Tachibana Takashi Awata 《Animal Science Journal》2013,84(3):213-221
Vertnin (VRTN) is involved in the variation of vertebral number in pigs and it is located on Sus scrofa chromosome 7. Vertebral number is related to body size in pigs, and many reports have suggested presence of an association between body length (BL) and meat production traits. Therefore, we analyzed the relationship between the VRTN genotype and the production and body composition traits in purebred Duroc pigs. Intramuscular fat content (IMF) in the Longissimus muscle was significantly associated with the VRTN genotype. The mean IMF of individuals with the wild‐type genotype (Wt/Wt) (5.22%) was greater than that of individuals with the Wt/Q (4.99%) and Q/Q genotypes (4.79%). In addition, a best linear unbiased predictor of multiple traits animal model showed that the Wt allele had a positive effect on the IMF breeding value. No associations were observed between the VRTN genotype and other production traits. The VRTN genotype was related to BL. The Q/Q genotype individuals (100.0 cm) were longer than individuals with the Wt/Q (99.5 cm) and Wt/Wt genotypes (98.9 cm). These results suggest that in addition to the maintenance of an appropriate backfat thickness value, VRTN has the potential to act as a genetic marker of IMF. 相似文献