水田氮素径流-侧渗-下渗流失特征模拟

基于水氮耦合平衡理论和田间实际观测,开发了一套既简单又综合的水田氮素流失特征模拟模型.模型模拟结果表明：氮转化速率常数经率定后能够准确表征水田尿素氮施入后在径流、侧渗和下渗等途径上的流失速率变化特征;同时由于氮素径流流失受自然环境干扰较大,其模拟准确度较低于下渗和侧渗.对黄斑土水田,在各个途径上单季累积模拟流失通量与田间观测结果较为吻合,误差均在20%以下,其中侧渗和下渗的误差小于10%.因此,可认为模型能对水田氮素多个途径的流失速率及通量进行有效模拟.     

A brief survey of computerized expert systems for crop protection being used in India

In the recent years, a plethora of computerized expert systems has been developed for various sectors of agriculture in India. The availability of low cost computers, agricultural knowledge and information technology professionals are the principal reasons for the development of so many agricultural expert systems. Among all agricultural expert systems, the expert systems for crop protection need special mention. These expert systems are meant to be used by farmers and other persons without much experience of using computers. Hence, special care must be taken while developing them. The current paper develops a taxonomy for the expert systems for crop protection and briefly discusses four such expert systems for crop protection being used in India.     

耐盐碱水稻新组合博优938的生物学特征和高产栽培技术

介绍广西钦州市农业科学研究所选育出的感光型杂交晚籼稻新组合博优938的主要生物学特征和高产栽培技术,为推广种植杂交晚籼稻新组合博优938提供参考.     

加快农业信息化建设为推进特色现代农业发展助力

阐述了新时期农业信息化的重要作用,探讨了如何以现代农业信息化综合服务推进农村信息化跨越式发展的问题,指出要利用现代信息技术为现代农业提供人才支撑。     

发挥公共图书馆阵地优势为“三农”提供优质服务

在分析公共图书馆为“三农”（农村、农民、农业）服务时存在问题的基础上,提出了几种具体的服务方式：     

独龙族和基诺族传统农业生产方式的比较

独龙族和基诺族都是我国人口最少的民族之一,地域分布、农业生产、文化习俗较为接近.本文采用实地调查、入户访谈和关键人物访谈的方法,从耕作方式、持续年限、作物品种等方面比较了两个民族传统轮歇农业的异同,进一步分析了其对保护生物多样性的贡献.     

安宁河流域杂交稻13612.5 kg/hm2配套技术研究

使用杂交稻品种“汕优63”在安宁河流域干热河谷稻区的云甸乡实施水稻高产攻关试验。栽培措施上采取两段育秧培育壮秧,确定适宜基本苗,宽窄行栽插合理密植,控制最高苗;施肥方式方法上磷肥与农家肥堆沤作底肥,氮肥“重底早追,前促中控后补”,钾肥在水稻生育中期重施,合理配方N：P：K为2．5：1：1．5,补施微量元素硅肥。经验收,产量达13612．5kg／hm^2。     

Introducing antisense <Emphasis Type="Italic">waxy</Emphasis> gene into rice seeds reduces grain amylose contents using a safe transgenic technique

Rice (Oryza sativa L.) eating quality is one of themost important traits. Amylose content (AC) in rice en-dosperm is a major index affecting rice eating quality[1,2].It has a negative correlation with gel consistency of rice[3].Based on amylose content, r…     

Genome-wide identification of R genes and exploitation of candidate RGA markers in rice

By scanning the whole genomic sequence of japonica rice using 45 known plant disease resistance (R) genes, we identified 2119 resistance gene homologs or analogs (RGAs) and verified that RGAs are not randomly distributed but tend to cluster in the rice genome. The RGAs were classified into 21 families according to their functional domain based on Hidden Markov model (HMM). By comparing the RGAs of japonica rice with the whole genomlc sequence of indica rice, we found 702 RGAs allelic between the two subspecies and revealed that 671 (95.6%) of them have length difference (InDels) in their genomic sequences (including coding and non-coding regions) between the two subspecies, suggesting that RGAs are highly polymorphic between the two subspecies in rice. We also exploited 402 PCR-based and co-dominant candidate RGA markers by designing primer pairs on the regions flanking the lnDels and validating them via e-PCR. The length differences of the candidate RGA markers between the two subspecies are from 1 to 742 hp, with an average of 10.26 hp. All related information of the RGAs is available from our web site(http://ibi.zju.edu.cn/RGAs/index.html).     

黄土高原地区资源,环境的持续发展问题与对策

本文根据黄土高原地区的资源优势和生态环境严重恶化的问题,提出了该区可持续发展的对策。