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81.
干旱区红小豆施肥效应研究 总被引:2,自引:0,他引:2
应用"3414"试验方案,研究了干旱区红小豆施肥效应和土壤供肥特性,以期为该区红小豆高产高效施肥提供参考依据。结果表明:施肥处理的红小豆产量高于不施肥处理,以N_2P_1K_1处理的红小豆产量和产投比最高。钾肥对红小豆的增产率最大,为13.7%~16.9%;其次是氮肥,增产率为6.1%~12.1%;最后是磷肥,增产率为0.6%~6.4%,即对红小豆产量影响的大小顺序为钾、氮、磷。由红小豆肥料效应方程可知,达到最高产量的N、P_2O_5、K_2O平均施肥量分别为98.5、109.0、97.5 kg/hm~2,产量为1 320 kg/hm~2,产投比为8.8;达到最佳产量的N、P_2O_5、K_2O平均施肥量分别为86.4、110.8、95.8 kg/hm~2,产量为1 302 kg/hm~2,产投比为9.0。此外,红小豆施肥试验期间,土壤地力贡献率为81.1%,土壤肥力中等,施肥效果明显。 相似文献
82.
【目的】研究小豆矮秆窄叶突变体(nld)的遗传行为及观察矮秆窄叶突变基因控制的农艺性状的变化。【方法】选用高秆小豆种质资源GM904与nld进行杂交,对亲本和F2、F3、F4各世代分离群体中个体形态进行调查统计,对株高、茎粗、主茎节数、第1至5节间长、前10节间长、单株粒数、百粒重、单株产量、荚长、荚宽、单株荚数等15个农艺性状进行调查分析。【结果】遗传分析结果表明,突变体中矮秆窄叶性状由一对隐性单基因控制。各性状间存在一定的显著或极显著差异,其中株高、茎粗、主茎节数、前10节间长、荚长、单株荚数的广义遗传力达到0.9以上,可作为小豆杂交育种的选择指标。【结论】矮秆窄叶突变基因导致株高变矮,叶变窄,茎变细,主茎节数减少,各节间长缩短,荚变小,产量显著降低。 相似文献
83.
云南省不同试验区小麦蚕豆间作的产量优势分析与评价 总被引:1,自引:0,他引:1
小麦蚕豆间作是云南省主要间作种植模式之一,具有提高产量,减少病虫害,提高养分、水分和光能利用效率等优势。本文基于2001—2010年本间套作课题小组40余组田间试验研究结果,对小麦蚕豆间作体系在云南陆良、玉溪、石林和昆明4个试验区的产量优势进行分析评价。结果表明:小麦蚕豆间作具有明显的增产优势。间作小麦比单作小麦平均增产1324%,间作蚕豆比单作蚕豆平均增产1480%,土地当量比(LER)平均值为114。但不同试验区的间作产量效应差异较大,其中玉溪、陆良和昆明试验区间作产量优势较大,LER分别为121,114和114。玉溪试验区间作产量优势主要来自于蚕豆,而其他试验区间作产量优势主要来自于小麦。 相似文献
84.
为了探索红小豆主要农艺性状与产量性状间的相关性,采用灰色关联和相关性分析的方法,对13个红小豆品种的11个主要农艺性状进行了研究。结果表明,11个农艺性状的变异系数为33.56%~2.37%,变异系数最大的为分枝数,最小的为生育期;灰色关联分析表明单株荚数、分枝数和生育期与单株产量关联度较高;相关分析表明单株荚数与单株产量呈显著的正相关。在红小豆辐射诱变高产突变体的选择中,首先应该把单株荚数作为选育的重点标识性状。 相似文献
85.
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87.
Nurun Nahar Khanam Junichi Kihara Yuichi Honda Toshihide Tsukamoto Sakae Arase 《Journal of General Plant Pathology》2005,71(4):285-288
When detached broad bean leaves were preinoculated with virulent strain B304 of Botrytis cinerea 24 h before a challenge inoculation with strain B304, lesion formation by B304 was significantly inhibited in red light but not in the dark. In leaves that were preinoculated with avirulent strain 021 and then challenged by B304, however, lesion formation was not inhibited even under red light. Such differences in lesion formation after the challenge inoculation with an avirulent strain were also observed with lesions caused by Alternaria alternata, a nonpathogen of broad bean and by avirulent strain 021R in the presence of germination fluid from spores of strains B304 and 021R. These results suggest the possibility that virulent B. cinerea produced a suppressor involved in induced susceptibility and an elicitor involved in resistance induced by red light during spore germination. 相似文献
88.
Size and composition of the weed seedbank was assessed after 12 years of application of four tillage systems in two crop rotations. Mouldboard and chisel ploughing at 45 cm, minimum tillage at 15 cm and no tillage were compared in continuous winter wheat and a pigeon bean/winter wheat 2-year rotation. Weed control was based upon post-emergence herbicide application. Weed seedling emergence from soil samples taken at 0–15, 15–30 and 30–45 cm depths was assessed in a non-heated glasshouse for 12 months. The tillage system influenced weed seedbank size and composition to a much greater extent than crop rotation. Total weed seedling density was higher in no tillage, minimum tillage and chisel ploughing plots in the 0–15, 15–30 and 30–45 cm layers respectively. Density in the whole (0–45 cm) layer did not differ significantly among tillage systems. With no tillage, more than 60% of the total seedlings emerged from the surface layer, compared with an average 43% in the other tillage systems. Crop rotation did not influence either weed seedbank size or seedling distribution among soil layers, and only had a small influence on major species abundance. The weed seedbank was dominated (>66%) by Conyza canadensis (L.) Cronq. and Amaranthus retroflexus (L.), which thrived in chisel ploughing and no tillage respectively. Results suggested that crop rotation and substitution of mouldboard ploughing by non-inversion tillage (especially by minimum tillage) would not result in increased weed problems, whereas use of no tillage might increase weed infestations because of higher seedling recruitment from the topsoil. 相似文献
89.
P. Oyarzun M. Gerlagh A. E. Hoogland 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(1):35-44
The relation between the frequency of legume crops in a rotation and the root rot severity in pea was examined in a field survey. Additionally, greenhouse experiments were performed with soil samples from legume rotation trials or from farmers' fields. The frequency of pea crops in current rotations proved to be much less than the recommended value of one in six years. The correlation between pea root rot and the number of years that pea or other legumes were not grown on the field under consideration (called crop interval) was weak. Root rot severity correlated better with the frequency of peas or legumes in general over a period of 18 years, but the frequency still explained only a minor fraction of the variation in disease index. Some experimental data pointed to the occurrence of a highly specific pathogen microflora with continuous cropping of only one legume species, but this phenomenon probably does not occur in farmers' fields. In field samples, root disease index for pea correlated well with that for field bean. The survival of resting structures of pathogens such asAphanomyces euteiches probably explains why the frequency of legume cropping has a higher impact than crop interval on root disease incidence. Pea-free periods and legume frequencies have a poor predictive value for crop management purposes. 相似文献
90.
This paper reports the results of a 2 × 2 factorial experiment on bush snap beans ‘Oregon 1604’. The treatments were 2 contrasted irrigation regimes and 2 contrasted plant densities, and were applied in 1978 and repeated in 1979. Data were collected on the number of flowers and pods, and pod size, at each node of the terminal inflorescence (6-T) of the main stem, and at each node of the oldest inflorescence (2-A) at Node 2. High and low plant densities were 45 and 18 plants m?2 in 1978 and 54 and 33 plants m?2 in 1979. High temperatures, frequently above 32°C, prevailed during bloom and pod development in 1978, but for the most part occurred only during the week prior to bloom in 1979. Inflorescences 6-T and 2-A usually formed 4 and 3 RN's, respectively, in 1978 and 3 and 2 RN's in 1979. The flowers at the proximal nodes of each inflorescence all opened within a few days of one another (duration of flowering at proximal nodes between 3 and 5 days); the flowering-periods of adjacent nodes overlapped, and the flowering period increased acropetally within the inflorescence (duration of flowering at distal nodes between 7 and 13 days). In general, number of flowers, pods formed, pods harvested and percent set decreased acropetally within each inflorescence. The rate of acropetal decline was lessened by high irrigation or low plant density. In both years, high irrigation increased the percent set of all RN's of the 2-A inflorescences, but few other consistent effects between years were observed. The 2 most proximal RN's together produced 93% or more of the yield of each inflorescence. High irrigation significantly increased the total number of pods harvested from these RN's of inflorescences 6-T and 2-A, and low density had a similar effect on 2-A. 相似文献