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131.
P deficiency is a major obstacle for crop production in subtropical red soils in South China, and the hydrolysis of organic P (Po) is of great significance in these soils due to the immobilization of P by Fe and Al. Cover cropping in orchards and symbiotic microbial inoculation are considered to improve soil quality, including P status, however, their effects on the hydrolysis of Po is little known. In this study, five soil managements were established in a guava orchard in South China for two and a half years, including clean culture (CC), cover cropping with Paspalum natatu (PN), PN with arbuscular mycorrhizal fungal inoculation (PNA), cover cropping with Stylosanthes guianensis (SG), SG with rhizobial inoculation (SGR). Soil chemical, biochemical and microbial properties were analyzed. Results indicate that soil pH and SOM content tended to increase following cover cropping alone or with microbial inoculation. Po content was significantly elevated in PNA. Po fractionation revealed that cover cropping alone or with microbial inoculation significantly affected the contents of moderately labile Po (MLPo) and moderately resistant Po (FAPo). Enzyme assay indicated that cover cropping with microbial inoculation increased the activities of acidic phosphomonoesterase (ACP), neutral phosphomonoesterase (NP) and alkaline phosphomonoesterase (ALP), with ALP the most sensitive, although ACP activity dominated in red soils. Correlation analysis suggested a significantly positive relationship between ALP activity and MLPo or FAPo. PCR-DGGE profile of the alp-harboring bacterial community showed that cover cropping with S. guianensis and mycorrhizal inoculation to P. natatu promoted the bacterial diversity and/or species richness. For almost all the measured parameters, PN and SG were comparable, however, PNA was superior to SGR, indicating the stronger additive effect of arbuscular mycorrhizal fungus than that of rhizobia. Cat-PCA indicated that MLPo was the most influential factor on phosphomonoesterase. In general, this study suggests that, in subtropical orchards with red soil, cover cropping with microbial inoculation can improve the Po hydrolysis via the promoted alp-harboring bacterial community and then ALP activity. Our results also suggest that the combination of P. natatu and arbuscular mycorrhizal fungus is better than S. guianensis and rhizobia, which possesses practical significance for sustainable production in these orchards. 相似文献
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133.
旨在为合理使用钝化剂及水稻糙米镉(Cd)含量与Cd在水稻体内富集和转移的关系提供一定的理论依据。从6种钝化剂中筛选出能够抑制糙米Cd积累的材料,通过对不同超标程度水稻组的产量、糙米Cd含量、各个器官对Cd的富集系数和转移系数进行统计分析,探讨不同钝化剂对Cd在水稻体内转移和富集的影响。结果表明:与对照相比,低、中浓度C材料和FA材料能够降低糙米中Cd浓度;FB材料和中、高浓度FD材料会促使糙米中Cd的积累。水稻各器官对Cd富集能力,无超标水稻为根茎米叶糠,超标水稻为根茎米糠叶;Cd向糙米的转移途径中,在不超标水稻组中糠—米的转移能力最强,在超标水稻组中叶—米的转移能力最强。 相似文献
134.
浅谈大田县政策性水稻种植保险现状及对策 总被引:1,自引:0,他引:1
大田县开展政策性水稻保险工作取得显著的成效。该文总结了大田县推进政策性水稻种植保险的意义、现状、存在问题,并提出今后完善政策性水稻种植保险的对策。 相似文献
135.
随着社会经济和城市建设的迅速发展,自然资源和生态环境等面临着巨大压力,矛盾日益突出,本文主要结合目前非常流行的低碳经济讨论了建设节约型的园林。 相似文献
136.
Dry heat parboiling is a unique paddy processing technique that has been scarcely exploited. Dry heat parboiling at high temperature for short time and low temperature for long time on physical and physicochemical properties of three rice varieties differing in amylose content were studied. Hardness of the kernels increased from 66.4 N, 68.8 N and 59.8 N in raw samples to 89.1 N, 86.9 N and 59.8 N in parboiled high amylose, low amylose and waxy rice samples respectively. Rapid migration and evaporation of water from severely heated kernels caused cavity formation at the centre. Irreversible damage of amylopectin structures to leachable fractions caused continuous rise of the pasting curve. Crystallinity was thereby reduced. Parboiled high amylose samples gave X-ray diffraction patterns with peaks characteristic of A, B and V-type starch crystallinity. Crystalline starch-lipid complexes were observed in low amylose and waxy rices. The significant increase in the amount of rapidly digestible starch from 56.7%, 61.7% and 66.6% in raw samples to 92.1%, 90.8% and 94.8% respectively in severely processed rice samples and subsequent reduction in resistant starch from 24.5%, 21.2% and 18.4% to 0.4%, 1.9% and 0.1% indicated possibilities for targeted food use of the dry heat parboiled samples. 相似文献
137.
138.
139.
中浙优8号在沙县作烟后稻种植表现及高产栽培技术 总被引:1,自引:0,他引:1
中浙优8号是中国水稻研究所和浙江勿忘农种业股份有限公司采用优质不育系中浙A与恢复系T-8配组而成的优质高产迟熟三系杂交稻新品种,经过3 a在沙县作烟后稻示范种植,表现群体整齐、分蘖力强、结实率高、米质较优、丰产稳产性好等特点。介绍其在沙县示范表现及高产栽培技术。 相似文献
140.
[目的]研究399对"一种两收"再生稻的影响。[方法]以适宜丘陵红黄壤种植的丰两优香1号、准两优527、宜优673再生稻品种为材料,分别设置喷施399和不喷施399(CK)2种处理,研究各处理对再生稻根系和产量的影响。[结果]结果表明:施用399使水稻在生育期上延缓成熟,且施后再生稻的总根系数量、白根数量、根鲜重、根干重、根体积大幅度增加,同时在两季总产量上准两优527、丰两优香1号和宜优673品种分别比对照增产6.39%、4.86%、5.94%。[结论]施用399有利于准两优527、丰两优香1号和宜优673再生稻品种再生根的发生。 相似文献