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101.
Five inbred lines, 10 single cross maize (Zea mays L.) hybrids and two standard cultivars as check were used to study the combining abilities and heterosis under three environmental
conditions. Random amplified polymorphic DNAs (RAPDs) markers were used to study the genetic diversity (GD) and further to
analyze relationship of RAPDs based GD with combining ability and heterosis in short duration maize. Spearman’s rank correlation
coefficients and linear regressions were analyzed to identify the most important factor determining heterosis and per se performance
of the hybrids. Variances due to general combining ability (GCA), specific combining ability (SCA) and their interactions
with environment were found to be significant. Twenty random primers generated 179 RAPD fragments. Of these, 102 RAPD fragments
were polymorphic. GD was determined using Jaccard’s similarity coefficient, and a dendogram was constructed by UPGMA cluster
analysis. The RAPDs based GD exhibited non-significant negative or positive association, non-significant linear regression
along with very low coefficient of determination (R
2) with SCA, high and mid parent heterosis (HP and MP) and per se performance of the hybrids. Significant positive correlations
and regressions along with high coefficients of determination were recorded for SCA with HP, MP and per se performance of
the hybrids. The HP and MP also established significant positive association and linear regression along with high coefficient
of determination with per se performance of hybrids whereas the parental mean did not establish any significant correlations
with the GD, HPH, MPH and grain yield of F1s. The present investigation, therefore, did not find any role of RAPDs based GD in determining hybrid heterosis and hybrid
performance in short duration sub-tropical maize. The SCA, however, has emerged as the most important factor in determination
of heterosis as well as per se performance of the hybrids in short duration maize. 相似文献
102.
103.
氮磷亏缺条件下杨树幼苗根系分泌酚酸的动态 总被引:1,自引:0,他引:1
采用循环收集装置收集杨树幼苗根系分泌物,采用超高压液相色谱法(UPLC)对根系分泌物中的酚酸含量进行测定。结果表明:在正常、缺N、缺P处理下杨树幼苗根系均能分泌对羟基苯甲酸、香草醛、苯甲酸和肉桂酸等酚酸类物质,养分缺乏显著促进杨树根系分泌酚酸。在缺N条件下,杨树幼苗较正常培养条件下酚酸分泌增加量为对羟基苯甲酸125%~263%、香草醛201%~316%、苯甲酸230%~332%、肉桂酸138%~188%,且根系分泌的各酚酸量随着胁迫时间的延长呈明显增加趋势,但3个培养时间段内(0~5天,6~10天,11~15天)酚酸分泌量差异未达显著水平(P>0.05);在缺P条件下,杨树幼苗较正常培养条件下酚酸分泌增加量为:对羟基苯甲酸96%~124%、香草醛58%~156%、苯甲酸222%~734%、肉桂酸99%~328%,其中,苯甲酸和香草醛的分泌量随胁迫时间的延长呈明显增加趋势,而苯甲酸和肉桂酸呈现先升后降的趋势。缺N、缺P处理下,杨树幼苗根系分泌酚酸的平均速率也存在一定差异,对羟基苯甲酸和香草醛在缺N条件下的平均分泌速率高于缺P培养,而苯甲酸和肉桂酸的平均分泌速率低于缺P培养。杨树幼苗在N,P缺乏条件下根系分泌酚酸... 相似文献
104.
105.
106.
Soil N mineralization is affected by microbial biomass and respiration, which are limited by available C and N. To examine the relationship between C and N for soil microbial dynamics and N dynamics, we conducted long-term laboratory incubation (150 days) after C and N amendment and measured changes in C and N mineralization, microbial biomass C, and dissolved C and N throughout the incubation period. The study soil was volcanic immature soil from the southern part of Japan, which contains lower C and N compared with other Japanese forest soils. Despite this, the area is covered by well-developed natural and plantation forests. Carbon amendment resulted in an increase in both microbial biomass and respiration, and net N mineralization decreased, probably due to increasing microbial immobilization. In contrast, N amendment resulted in a decrease in microbial respiration and an increase in net N mineralization, possibly due to decreased immobilization by microbes. Amendment of both C and N simultaneously did not affect microbial biomass and respiration, although net N mineralization was slightly increased. The results suggested that inhibitory effect on microbial respiration by N amendment should be reduced if carbon availability is higher. Thus, soil available C may limit microbial biomass and respiration in this volcanic immature soil. Even in immature soil where C and N substrate is low, soil C, such as plant root exudates and materials from above- and belowground dead organisms, might help to maintain microbial activity and N mineralization in this study site. 相似文献
107.
锦屏县毛竹现状分析与产业发展对策 总被引:1,自引:0,他引:1
毛竹产业的发展必须以市场为导向,以增加农民收入和促进山区农村经济发展为目标,创新发展方式,加大扶持力度,按照规模上求大、品种上求新、管理上求精的要求,坚持扩大面积与提高种植质量并重,强化科技支持与产业经营体系建设,把毛竹子产业培育成山区经济发展的重要支柱产业。 相似文献
108.
Zhengong Yin Huidong Qi Qingshan Chen Zhanguo Zhang Hongwei Jiang Rongsheng Zhu Zhenbang Hu Xiaoxia Wu Candong Li Yong Zhang Chunyan Liu Guohua Hu Dawei Xin Zhaoming Qi 《Plant Breeding》2017,136(5):688-698
Plant height is closely related to seed yield of soybean. The goal of this study was to identify important loci affecting soybean plant height using meta‐analysis based on a reference physical map. Plant height related to QTLs was mapped across eight years with a RIL population by WinQTLCart v2.5. 182 QTLs related to plant height of soybean from database and our research were collected, and each QTL was projected onto the soybean physical map by software BioMercator v2.1. The confidence interval of meta‐QTL ranged from 0.09 to 5.07 Mb, and the mean phenotypic variance ranged from 4.9% to 73.0%. Furthermore, 4,259 candidate genes were located in these consensus QTLs, and 40 of them were involved in the plant growth and stem elongation and annotated as plant hormone signal transduction (pathway ID ko04075) in KEGG pathway. These results would lay a foundation for fine mapping of QTLs/genes related to plant height and marker‐assisted selection for breeding in soybean. 相似文献
109.
Sun Lifei Sang Changpeng Wang Chao Fan Zhenzhen Peng Bo Jiang Ping Xia Zongwei 《Journal of Soils and Sediments》2019,19(10):3499-3511
Journal of Soils and Sediments - The responses of N2O emission to increasing temperature in different soil horizons are not clearly understood yet. Here, we investigated the effects of increasing... 相似文献
110.
Niel Hens Christel Faes Marc Aerts Ziv Shkedy Koen Mintiens Hans Laevens Frank Boelaert 《Journal of Agricultural, Biological & Environmental Statistics》2007,12(4):498-513
Modeling infectious diseases data is a relatively young research area in which clustering and stratification are key features.
It is not unlikely for these data to have missing values. If values are missing completely at random, the analysis on the
complete cases is valid. However, in practice this assumption is usually not fulfilled. This article shows the effect of ignoring
missing data in modeling the force of infection of the bovine herpesvirus-1 in Belgian cattle and proposes the use of weighted
generalized estimating equations with constrained fractional polynomials as a flexible modeling tool. 相似文献