如何保护稻田蜘蛛

蜘蛛能捕食害虫，稻田蜘蛛有草间小黑蛛、食虫瘤胸蛛、拟环级狼蛛，拟水狼蛛、稻田水狼蛛、八斑球腹蛛等10多种，占稻田蛛总数量70％－90％。保护和利用蜘蛛防治害虫是生物防治的一项措施。1稻田蜘蛛在越冬和较大的农事活动中损失很大。如果是犁田过冬，则使田间有较多的空隙，可为田间蜘蛛提供较好越冬场所；如果采用田埂留条草，先灌水后犁田或把田，或留做秧田的地块，可保护蜘蛛源。2稻田蜘蛛需水，但又怕深水。如稻田水放干，蜘蛛为生活找水会离开稻田；如果稻田灌深水，蜘蛛则为找浅水，也会离开稻田。因此，应根据水稻和蜘蛛的需水情…     

稻蟹共养对水稻有害生物控制效果评价

稻田综合种养殖是一种新型的农业生产技术模式,稻蟹共养在辽宁省盘锦市已推广了近20年,不仅能生产优质稻米,还出产肥美河蟹,经济效益显著增加。本文以稻蟹共养田生物多样性对稻田有害生物防控效果为切入点,通过对比稻蟹田和常规田优势天敌群落的组成情况,考察河蟹、天敌生物对水稻主要病虫草害的影响程度,结果表明,蜘蛛作为稻田捕食性天敌优势种类,稻蟹田的蜘蛛个体总数量显著多于常规田,约为1.77倍,而蜘蛛种类数没有差异;稻蟹田稻瘟病发生重于常规田、纹枯病发生与常规田相当、稻飞虱发生量略轻于常规田、杂草发生量略轻于常规田。总之,稻蟹共养因投入河蟹而不施用农药,客观上能涵养天敌生物,增强系统内部生物多样性程度,使生物间联系更加紧密,充分发挥了生物间相互协调与制约的关系,结合抗病虫水稻品种应用,从而在一定程度上对稻田有害生物发挥较好的防控效果。     

水稻有害生物生态调控的理论与实践

针对水稻重大病虫害防治问题和农药污染造成的生态问题，从生态学观点出发，阐述了有害生物生态调控的形成及其理论基础。为了农业的可持续发展，在生产实践中研究和探讨了有害生物生态调控的多项技术措施及其控害效果。结果表明：经济作物与高产优质水稻连作种植模式及其农田景观多样性耕作制，可显著的影响与它关联的害虫及其天敌在种群数量上的变动，并促使田间生物群落发生变化，从而导致水稻主要害虫种群对稻田生态环境的非适应性减少，而蜘蛛等天敌种群则适应性增加，生物多样性指数提高。与此同时，在水稻高产栽培中坚持合理施肥控制施氮量，利用水稻品种多样性混合间栽。开展稻鸭生态种养，应用频振式杀虫灯等措施，都能显著减少稻田主要病虫的发生和危害。实现有害生物的可持续治理。     

海南植胶区不同群落结构林下生物多样性分析

通过样方调查的方法分析海南植胶区4种不同特点、不同气候带及不同地形的林下植被生物多样性。结果表明，4种植被林(包括幼龄橡胶林、老龄橡胶林、桉树人工林、天然次生林)中，物种数由高到低分别为老龄橡胶林(44种)＞幼龄橡胶林(41种)＞天然次生林(39种)＞桉树人工林(30种)；不同气候带林下物种组成及生物多样性指数差异较大，表现为湿润气候带以需水量大的草本植物，干旱半干旱地区以适应性强的植物为主，且湿润气候带的物种优势度指数和丰富度指数高于干旱、半干旱气候带，而多样性指数和均匀度指数则相反；其次，平原台地与山丘地区的4种群落类型下物种优势度λ均具有一定的差异，整体表现为天然次生林＞老龄橡胶林＞幼龄橡胶林＞桉树人工林。     

海南三亚和文昌稻田蜻蜓目成虫群落调查分析

蜻蜓目（Odonata）昆虫生活在不同的湿地中,越来越多地被用作评估环境质量及其变化的生物指标。弄清海南稻田蜻蜓目成虫群落组成和种群发展动态,可以为评价海南稻田环境质量提供依据。本研究于2017年对热带地区三亚市和亚热带地区文昌市的第1季和第2季稻田蜻蜓进行抽样调查,结果显示：蜻蜓群落在海南两季水稻不同生长期都稳定存在,种类有5~15种,数量为每百丛(3.70±0.67)~(14.00±0.57)头。蜻蜓群落多样性指数（H′）为2.007~2.193,均匀性指数（J）为0.786~0.808,优势集中性指数（C）为0.148~0.190。三亚和文昌分别采集到蜻蜓成虫3科15种和2科17种,第2季种类多于第1季,共有物种11种,两季群落相似系数（C_s）为0.701,优势种相似系数（C_s）为0.857。在三亚两季的分蘖期、花期和结实期个体数量有显著差异,而文昌两季不同时期个体数量无显著差异。三亚位于南繁区,杯斑小蟌（Agriocnemis femina）、翠胸黄蟌（Ceriagrion auranticum）和截斑脉蜻（Neurothemis tullia）可能是对南繁稻田环境变化敏感的种类。     

Characterisation of spatial patterns of regional paddy rice with time series remotely sensed data

Remote sensing has facilitated the identification of acreage and spatial distribution of field crops with obvious seasonal dynamics. The primary objective of this study is to identify the spatial patterns of double-season early rice, single-season middle rice and double-season late rice of Hunan Province and Yuanjiang City, China, in 2010, using two kinds of time series remotely sensed imagery: 8-day composite MODIS surface reflectance product data (MOD09A1) and HJ-1A/B satellite images with a 4-day revisit period. The available MODIS and HJ-1 CCD images of transplanting and heading stages were first assured in accordance with the schedules of local traditional paddy fields tillage. Based on the MOD09A1 data product, time series normalised difference vegetation index (NDVI) images were calculated and smoothed to remove the noise and the atmospheric effects. Second, the spatial distribution and planting acreage of three types of rice of Hunan Province were derived from combining the enhanced vegetation index and land surface water index according to the water background and variation characteristics of NDVI values at transplanting and heading stages. Conversely, a two-test procedure was used to finish the identification of paddy rice in Yuanjiang City using time series HJ-CCD imagery. The first test was to derive the potential rice pixels using the NDVI image (?NDVI) between heading and transplanting stages, and the second test was to remove the non-rice pixels using maximum likelihood supervised classification. The experimental results showed that three types of rice were mainly distributed along the Dongting Lake Basin in Hunan Province and the relative errors were ?10.99, 1.46 and ?5.87 %, respectively, while they were primarily planted in the northern plains of Dongting Lake in Yuanjiang City, where the relative errors were 12.1, 16.7 and 0.8 %, respectively. We conclude that transplanting and heading stages are the best phenological combinations for identifying paddy rice through remote sensing time series analysis, and this study can provide a basis for evaluating paddy rice yield on a large scale .     

Factors affecting differences in the rainy season rice yield in a lowland area of a mountainous village in Lao PDR

The unevenness of rice productivity in lowland areas is caused by differences in farming techniques, accessibility of water, planting environment, and other field-specific factors. In order to increase rice production in low-productivity fields, this study examined the factors affecting yield reduction. In this study, the influence of water conditions, farming activities, and soil fertility on rice yield were analyzed in a lowland area located in the northern part of Lao PDR. A field survey was conducted in a village in Vientiane Province during the rainy season of 2013. Water conditions were observed (i) prior to land preparation, (ii) between land preparation and transplanting, and (iii) after transplanting. Farming activities were recorded in each lowland rice field weekly from June to August. Yield surveys were also conducted in 47 field blocks, and soil samples were collected for soil fertility analyses. The ponding of fields commenced in the middle of June, and extended from the upper part to the lower part of the lowland area. Transplanting was conducted following the distribution of surface water, and no serious water shortages were observed after transplanting in the surveyed areas. There was no correlation between grain yield and the content of total nitrogen or available phosphorus in the field soil. Significant differences in grain yield were detected between direct and plot-to-plot irrigation, early and late ponding, and transplanting in July and in August. The results suggest that water shortages and the delay of field ponding before land preparation led to late transplanting which caused yield reduction.     

晚播晚栽机插水稻群体生长特征及其调控策略

目的 探究水稻机械化移栽应用中长期存在的晚播晚栽机插稻的特殊应用价值,方法 在苏南设置大田试验,分析了晚播晚栽机插水稻的产量表现及其群体生产特征,并设置密度和穗肥施用处理,解析栽培措施对晚播晚栽机插水稻群体发育和产量形成的影响。结果 机插水稻晚播晚栽产量出现一定程度的下降,主要原因是单位面积穗数和每穗粒数降低。晚播晚栽机插稻群体高峰苗出现时间相对前移,茎蘖成穗率则明显下降。同化物质积累和运转均受到一定影响,抽穗期茎鞘中非结构性碳水化合物积累下降,茎鞘物质输出率和转换率也呈下降趋势。可见,晚播晚栽机插水稻存在物质生产和产量形成的必然劣势。增加栽植密度,单位面积穗数显著增加,干物质积累量上升,产量明显提高。在同一密度条件下,随着穗肥施氮量水平的提高,产量表现为先上升后下降的趋势,过多穗肥施用不利于晚播晚栽机插稻结实期的物质积累。较高密度配合适宜水平的穗肥施用,可提     

浙江省水稻精量机械穴直播技术研究与示范

为促进直播技术在浙江省水稻生产上的应用,进行精量机穴播、撒直播、手插秧等不同种植方式的比较试验,同时进行水稻机穴播的生产示范。研究结果表明,在机穴播密度为23.5万hm2时,杂交籼稻内2优6号、杂交粳稻甬优9号和甬优12的产量和手插秧相近,都显著高于撒直播;机穴播的优势在于分蘖发生早且多,与手插秧相比,内2优6号、甬优9号和甬优12机穴播的每穗粒数分别降低7.92%、24.88%和15.68%,但有效穗数分别增加11.75%、21.92%和31.11%。2012年和2013年进行水稻机穴播生产示范,内2优6号、甬优9号和甬优12的平均产量分别达到9 667.6 kg/hm2、12 285.0 kg/hm2和12 294.8 kg/hm2,进一步说明水稻机穴播高产的可行性。     

不同超级稻品种产量形成及其氮素吸收差异研究

以江西省水稻生产上推广的几个超级早稻、超级晚稻品种为材料,研究了长江中下游双季稻区不同超级稻品种产量形成、干物质生产及其氮素吸收特性。结果表明,同一栽培条件下,不同超级早、晚稻品种间干物质生产与转运、产量形成及氮素吸收存在一定的差异,生产100 kg籽粒所需的氮量差异不大。相关分析表明,超级早、晚稻总干物质积累量、茎叶干物质输出率和转换率与其产量均呈显著正相关。适宜在江西地区种植的超级早、晚稻品种分别为陆两优996、金优458和钱优1号、天优华占。     

双季稻机插技术在江西的应用现状、存在问题及推广对策

利用江西省双季稻区8个县24个乡镇的调查数据,对双季稻机插技术在江西的应用现状、存在问题进行了研究。结果表明,机插种植方式的成本低于其他种植方式、收益高于其他种植方式;机插种植方式的推广受到农户的年龄、文化程度、土地规模、资金等的影响,年龄越小、文化程度越高、土地经营规模越大的农户机插比例相对较高;限制机插技术推广的主要因素包括育秧技术复杂、购机及机插费用高、田块小和分散等;积极推进土地集约化进程、加强机插核心技术的培训指导力度、建立稳定的政策资金扶持机制、创新机插服务模式、积极宣传并做好示范区建设等是促进机插技术推广的重要举措。     

Studies on Plant Population and Stand Establishment Techniques for Increasing Productivity of Rice in Dera Ismail Khan, Pakistan

Rice production in Pakistan is constraint by many factors pertaining to prevalent planting techniques. A research on the feasibility of new planting techniques (direct seeding on flat, transplanting on flat, direct seeding on ridges, transplanting on ridges and parachute planting) in transplanted and direct wet-seeded rice was undertaken at Dera Ismail Khan region of Pakistan’s North West Frontier Province during 2002 and 2003. Among the planting techniques, the best performance for the yield formation and economic evaluation was noted for transplanting on flat during both years. Chinese parachute planting technology also showed very promising results in most of the parameters. Direct seeding on ridges could not excel transplanting on flat and parachute planting during both cropping seasons. The findings concluded the feasibility of parachute planting technology along with traditional rice transplanting on flat over all other planting techniques being practiced in the area.     

安徽安庆混作稻区稻纵卷叶螟第三、四代发生规律研究

对2007年安徽安庆单双混作稻区第3、4代稻纵卷叶螟发生规律的系统研究表明,第3、4代稻纵卷叶螟在安庆混作稻区有两个发生高峰期,单季早中稻在7月下旬至8月初,双季晚稻在8月下旬末至9月上旬。结合雌蛾卵巢解剖和灯诱数据,进行世代性质分析。结果表明,早中稻田第3代以本地繁殖世代为主,有部分迁入;第4代为本地虫源,大部分迁出,少部分滞留为害。对比两种不同类型稻田的第4代稻纵卷叶螟雌蛾卵巢解剖数据,发现安庆稻区单季早中稻稻纵卷叶螟第4代以迁出型为主,双季晚稻田为居留型,早中稻田稻纵卷叶螟除远距离迁飞外,也可直接转移扩散到附近晚稻田中滞留为害。滞留的原因包括两方面,一是近年来暖秋（9月份）频率增大;二是安庆单双混作稻区的栽培制度和水稻品种的变革,使得单季稻比例上升,水稻在生长季节中不间断地种植,为稻纵卷叶螟的栖居、繁殖和秋季滞留为害提供了条件。     

粤北稻区稻纵卷叶螟的发生规律及虫源性质分析

采用田间系统赶蛾、雌蛾卵巢解剖的方法研究了2010-2011年韶关地区稻纵卷叶螟的种群动态及各发生世代的虫源性质,并结合1961-1976年、2000-2011年曲江地区稻纵卷叶螟高峰日和高峰日蛾量,分析了不同年份稻纵卷叶螟田间种群消长的差异性。1)韶关地区稻纵卷叶螟一年可发生6个世代,早稻发蛾高峰期集中在6月上中旬,晚稻发蛾高峰期集中在8月底至9月上旬;2)明确了韶关地区稻纵卷叶螟各发生世代的虫源性质;3)在1961-1976年和2000-2011年两个时间段之间,曲江地区稻纵卷叶螟早稻和晚稻田间蛾量高峰日差异不显著,但2000年以来早稻田间高峰日平均蛾量却显著高于20世纪60-70年代;4)2000-2011年,曲江地区稻纵卷叶螟田间蛾量的最高峰在早稻期间的出现频率高于晚稻,早稻和晚稻的主害代分别为第3代和第6代,但个别年份第2代、第7代稻纵卷叶螟也会暴发成灾。可见,2003年全国稻纵卷叶螟大暴发以来,前期迁入蛾量的成倍增加直接导致了粤北地区早稻稻纵卷叶螟连年大发生,而秋季回迁虫源则受北方稻区的自然环境和人为防治因素的干扰,与前期迁入量之间并没有必然的联系。