粳稻品种抗稻瘟病性与其生物学性状的相关关系研究

对３４２份粳稻材料进行抗稻瘟病性（抗叶瘟、穗颈瘟）与其生物学性状（株高、穗长、每穗粒数、分蘖率、单株有效分蘖数、空秕率、着粒密度，以及成熟期等）相关关系研究，结果不同品种（系）间存在着一定差异。抗叶瘟性与株高、穗长、每穗粒数、单株有效分蘖数、着粒密度呈显著正相关，相关系数依次为：０．４０９、０．４９１、０．４２６、０．６５７、０．４７１；与空秕率呈显著负相关，相关系数为－０．５９１。抗穗颈瘟性与株高、每穗粒数、单株有效分蘖数呈显著正相关，相关系数分别为：０．７１７、０．４６２、０．３６２；与空秕率、分蘖率、着粒密度呈显著负相关，相关系数依次为：－０．３４３、－０．３３２、－０．４７６。试验表明，株高、单株有效分蘖率、每穗粒数、空秕率等性状，可做为主要标记，在粳稻品种（系）抗稻瘟病性选鉴上应用     

玉米青枯病病原腐霉对其伴生镰刀菌的影响

 本试验以玉米青枯病病原肿囊腐霉(Pythium inflatum Malthews)与禾生腐霉(Pythium gramlnicola Subram)为材料,着重研究了两种腐霉的生长与代谢对其伴生病原禾谷镰刀菌(Fusarium graminearum Schw.)的影响,结果表明:1.腐霉的定殖生长能力弱于禾谷镰刀菌。在腐霉菌落上,禾谷镰刀菌仍可生长,而在禾谷镰刀菌菌落上,腐霉则不能生长。2.在伴生条件下,腐霉被镰刀菌覆盖的时间长短随接种间隔而有变化,接种间隔愈短,则覆盖愈快。3.两种腐霉的培养滤液均对禾谷镰刀菌的孢子萌发与芽管伸长及菌落扩展有明显的促进作用,表明滤液中含有对镰刀菌生长有利的活性成分。4.腐霉培养滤液对禾谷镰刀菌红色色素的产生有一定的抑制作用,其原因可能与腐霉的嗜糖性有关。5.田间结果表明,腐镰复合接种的发病率接近禾谷镰刀菌单菌接种,但低于腐霉单菌接种。     

浙江地区不同品种紫花苜蓿不同刈割期二茬性状表现

对不同秋眠级别的紫花苜蓿Medicago sativa品种进行适应性试验,研究不同品种不同刈割期株高、分蘖数、根系、茎叶比及生物学产量间的变化,为生产推广提供指导.     

西兰花品种比较试验

本试验引进了沪绿68、沪绿88和沪绿118共3个西兰花新品种,与当地主栽品种——耐寒优秀进行比较试验,试图筛选出适应当地种植的西兰花新品种。试验结果表明,沪绿68花球紧实度不高且蕾粒容易掉;沪绿118植株侧枝很多且花球有空心;沪绿88品种长势好、商品性好,适宜在如东地区种植。     

Simulating farming practices within a region using a stochastic bio-decisional model: Application to irrigated maize in south-western France

Agricultural is a major contributor to environmental resource management problems. Modelling the distribution of agricultural land use to evaluate current situations or scenarios is an important issue for policy-makers and natural resource managers. A promising approach is the use of bio-decisional models based on decision rules. However, at the regional scale, the large number of farmers makes it difficult to identify decision rules, and the diversity of farmers' decisions is rarely considered. To this end, we developed SIMITKO, a spatialised and stochastic bio-decisional model, able to simulate the spatial and temporal variability in farming practices. We focused on the choice of varietal earliness and sowing practices of maize (Zea mays L.) in the Baïse sector (south-western France). Model development was based on statistical analyses of surveys of farmers’ practices to identify their current strategies, the best variables to describe the practices and the probabilities associated with the values of the variables for each strategy. We tested SIMITKO by simulating the dynamics of areas sown with maize. Comparing model predictions of practices to observed data showed generally good predictions of sowing dynamics but less satisfactory predictions of varietal earliness choices. Possible improvements are suggested.     

Mechanisation of organic fertiliser spreading,choice of fertiliser and crop residue management as solutions for maize environmental impact mitigation

The environmental impact of crop production is mainly related to fossil fuels consumption and to fertilisers application. Emissions arising from the spreading of organic and mineral fertilisers are important contributors for impact categories such as eutrophication and acidification. The choice of the fertilisers and of the spreading techniques as well as the crop residues management can deeply affect the environmental impact related to crop cultivation.In this study, seven scenarios describing fertilising schemes characterised by different organic and mineral fertilisers and by different mechanisation were compared. The aim is to evaluate, using the Life Cycle Assessment (LCA) method, how the environmental performances of grain maize production were affected by these different fertilisers schemes. The study was carried out considering a cradle to farm gate perspective and 1 t grain maize was selected as functional unit. Inventory data were collected on a farm located in Po Valley (Northern Italy) during year 2013 and were processed using the composite method recommended by the International Reference Life Cycle Data System (ILCD). The compared scenarios involved organic and mineral fertiliser distribution and were: pig slurry incorporation after >3 days after spreading (BS), fast pig slurry incorporation within 2 h from spreading (AS1), direct soil injection of pig slurry (AS2), pig slurry incorporation (after >3 days) with straw collection (AS3), digestate spreading instead of pig slurry (after >3 days) (AS4), only mineral fertilisers (i.e. urea and superphosphate) distribution (AS5) and only mineral fertilisers (i.e. calcium ammonium nitrate and superphosphate) distribution (AS6).The results were not univocal, since climate and soil conditions as well as physical and chemical fertiliser characteristics differently affected the environmental load, especially for particulate matter formation, terrestrial acidification and terrestrial eutrophication impact categories. AS1 and AS2 showed the most beneficial results for these impact categories (between ↙67% and ↙73% respect to worst scenario). AS6, on the opposite, showed the highest environmental impact for those impact categories mainly affected by energy and fossil fuel consumption (climate change, ozone depletion, human toxicity with carcinogenic effect, particulate matter, freshwater eutrophication, freshwater ecotoxicity and mineral, fossil and renewable resources depletion), categories on which AS3 and AS4 were the best solutions. AS3 was the most impacting for terrestrial acidification and eutrophicationA sensitivity analysis was carried out varying grain maize yield (mostly affected: marine eutrophication) and ammonia volatilisation losses due to organic fertilisers (mainly affected: terrestrial acidification and eutrophication).The achieved results can be useful for the development of ⬓spreading rules⬽ that drive the application of organic fertilisers in agricultural areas where there is an intense livestock activity.     

毕节市漆树品种产量与树皮性状的灰色关联度分析

为漆树优良品种的选择以及灰色系统理论在林业林木品种评价上的运用提供参考，对毕节市8个漆树品种红漆大木、粉皮大木、灯台大木、红尖大木、肤胭皮、粉红皮、白杨皮、青杠皮等树皮解剖中6个主要性状与产漆量的关系进行灰色关联度分析。结果表明：漆树树皮解剖的单个性状对产漆量有直接影响，其中以漆汁道直径的大小关系最重要，直接关联度达0．7964；其次是活皮漆汁道单位面积与活皮厚度。从树皮解剖的综合性状看，漆树品种最好的依次是红尖大木＞红漆大木＞肤胭皮＞灯台大木＞白杨皮＞粉皮大木＞粉红皮＞青杠皮。分析结果与实际生产基本一致，表明在林业生产中运用灰色关联分析进行综合评价是可行的。     

水肥耦合对小麦/玉米带田产量及构成因素的影响

采用"3414"最优回归设计方案,于2007-2008年在甘肃省农业科学院张掖节水试验站,开展不同水肥耦合处理小麦/玉米带田产量效应研究。结果表明,不同水肥耦合模式对小麦/玉米带田产量的影响较大,其差异达极显著水平。其中,氮肥对产量的贡献最大,水分次之,磷肥最小,氮肥对带田混合产量的绝对贡献率达79.4%,而水分对带田混合产量的绝对贡献率达为52.9%;水肥耦合效应为:水氮耦合水磷耦合氮磷耦合;获得高产量12 952.5~13 880.0kg/hm2的施氮量为420~630kg/hm2、灌水量为5 550~6 750m3/hm2、施磷量为120kg/hm2。相关分析表明,施氮量和灌水量与间作玉米的穗粒数、千粒质量、穗粒质量、株高均呈极显著正相关,施氮量与间作小麦的穗粒质量、穗粒数呈极显著正相关。     

硼肥用量对玉米生长发育及产量的影响

以郑单958和豫单606为试验材料,采用盆栽试验方法,探索不同硼肥用量对玉米产量及生长发育的影响。结果表明,施用适量硼肥可促进玉米生长发育,显著提高叶面积指数,使植株干物质积累量增加,同时硼肥能够促进干物质向果穗运输。施用硼肥能够促进玉米穗分化,使雌雄间隔期缩短,显著提高花丝数和花丝生长速率,进而增加穗粒数。施用硼肥显著提高玉米产量,且不同用量对其影响不同,3.33 mg/kg土壤硼肥处理的效果最为显著,郑单958和豫单606分别较不施硼肥处理增产14.3%和17.4%;施用量为13.3 mg/kg时郑单958增产3.5%;豫单606产生中毒症状,产量较对照降低4.4%。