基于典范对应分析PPC生物降解膜覆盖条件下土壤温度、相对含水量的综合分析

为探讨PPC黑色、白色全生物降解膜与普通黑、白地膜不同类型地膜覆盖对旱地花生田土壤水分和温度变化动态的影响,以露地栽培为对照,测定了不同类型地膜覆盖垄作花生各生育时期耕层土壤温度和土壤相对含水量(0~15 cm)变化情况.结果 表明:全监测期内,PPC白色全降解膜地表(0 cm土层)和5 cm土层平均温度分别比对照提高1.24℃和0.62℃,15 cm处地温差异较小.覆盖地膜对0 cm土层土壤温度日平均变幅影响最大,最大变幅达7℃.覆膜处理相同土层土壤相对含水量均比对照有所增加,土层越深,相对含水量越高.基于典范对应分析法对土壤温度和相对含水量进行综合评价,结果显示,不同处理在14:00点时对土壤温度和相对含水量的影响均较大.     

移栽地膜棉覆膜期土壤温湿度的变化特点

试验结果表明，移栽地膜棉田覆膜期间，土壤温度比常规移栽棉提高２～５℃，且增温效果随着外界气温的升高和光照时间的延长而增大；可使棉田耕层土壤保持适宜的土壤水分，并使耕层土壤水分的变化程度减少；移栽地膜棉棉田的增温保墒作用均随土层加深而减弱。其栽培技术上应注重适时揭膜、科学施肥和加强调控等     

棉花聚垄施肥生态效应栽培技术研究

研究了不同垄作集肥方式对棉田土壤生态环境及棉田病虫害的影响。结果表明,垄作栽培能提高0~20cm土层的土壤温度,降低土壤容重,提高土壤孔隙度和通气性,改善棉田生态环境,减轻病虫害发生。适宜的垄高为15cm。垄作棉花早生快发,稳长增蕾铃,与平作散施肥对比,株铃数、铃重增加,霜前花率提高,极显著提高了产量。     

新国标地膜在棉花栽培上的应用及回收探讨

为推动新国标地膜回收利用,减少土壤残膜污染,以棉花新国标地膜覆盖和无膜覆盖为研究对象,研究其对土壤温度、棉花地上部鲜重和干重、株高、产量的影响.结果 表明:在棉花生长的前两个月,地膜对土壤的增温作用明显,土壤5 cm和10cm深处的增温幅度分别为0.25℃～8.25℃和0℃～6.87C;在棉花封行时,地膜的增温作用已基本消失,此时适合揭膜;覆膜能够增加棉花地上部鲜重、干重和株高,显著增加棉花产量(覆膜比不覆膜增产籽棉量38.68％).     

旱作区生物降解膜对土壤温度、水分及春小麦产量的影响

为探索旱作区生物降解膜对春小麦的影响,在甘肃兰州对春小麦进行了生物降解膜、普通地膜和露地栽培条件下,土壤温度、水分和小麦产量的检测和分析。结果表明,生物降解膜和普通地膜处理下,春小麦全生育期0~25 cm土层土壤温度比露地高0.78 ℃和1.84 ℃;在小麦苗期-抽穗期,两种覆膜处理对地温的影响无显著差异,小麦抽穗之后,生物降解膜对土壤的增温效果显著低于普通地膜;小麦抽穗之前,两种覆膜处理下土壤日温度变化趋势差异不明显,抽穗期及后期生物降解膜处理日温度变化趋势与露地无差异。0~200 cm土壤含水量在小麦苗期-抽穗期,两个覆膜处理间差异不显著,均显著高于露地处理;在开花期-灌浆期,生物降解膜处理显著高于露地、低于普通膜处理;在成熟期,生物降解膜处理较普通地膜处理无显著差异,显著高于露地。两种覆膜处理小麦的产量无显著差异,均显著高于露地处理,分别较露地增加 24.03%和32.72%。综上所述,在旱区春小麦栽培中,以生物降解膜代替普通地膜是可行的。     

全膜覆盖双垄集雨沟播种植马铃薯的效益分析

在降雨量400 mm左右的原州区开城镇寇庄村,对晋薯7号进行了不同覆膜方式的研究,测定了0～20 cm土层地温和0～100 cm土壤含水量,以探索全膜覆盖双垄沟播栽培技术对土壤温度和含水量的影响。结果表明:在马铃薯生长的每一个时期,不同土壤深度的地温和有效积温总体表现为:秋季全膜双垄沟播栽培>顶凌全膜双垄沟播栽培>播期全膜双垄沟播栽培>秋季半膜栽培>顶凌半膜栽培>播期半膜栽培;不同处理土壤含水量是秋季覆膜栽培>顶凌覆膜栽培>播期覆膜栽培,全膜覆盖栽培>半膜覆盖栽培。播期半膜栽培马铃薯667 m2产量为1 436.9 kg,而秋季全膜覆盖双垄沟播栽培667 m2产量达到1 762.7 kg,增产效果非常显著。     

新疆地区棉花生育期揭膜与否对黄萎病发生的影响

为探索新疆机采棉收获后才揭膜栽培模式下与滴水前揭膜的黄萎病发病率有无变化,对棉花生产有无影响.在新疆生产建设兵团第一师农业科学研究所2号地进行试验.结果 表明,生期期不揭膜黄萎病发病高峰期时的发病率和病指高于对照,但差异不显著;生育期不揭膜处理的土壤0 ～ 10 cm土层温度增加、含水量略降、电导率明显降低;生育期不揭膜处理的总产量高于对照,差异显著;纤维品质总体好于对照,个别项目差异显著.究其原因,生育期不揭膜降低了土壤后期返盐程度和电导率.     

秸秆覆盖对黑土区大豆生长及产量构成因素的影响

为研究秸秆覆盖对黑土区土壤水热及大豆生长状况的影响，以垦丰16为试验材料，基于大田试验，分别设置秸秆表面覆盖(T1),0～10 cm土层秸秆还田覆盖(T2),10～20 cm土层秸秆还田覆盖(T3)和无秸秆覆盖(CK)4种处理。通过测定大豆生育期内的耕作层土壤温度及含水率，以及大豆株高、茎粗和叶面积等生长指标，对比分析不同秸秆覆盖处理对土壤水热、大豆生长及产量等性状的影响。结果表明：大豆生育期初T1处理0～10 cm土层含水率明显高于T2及T3处理；在10～20 cm差异逐渐缩小，20～30 cm土层差异变大；秸秆覆盖会影响播种初期的出苗率，而在播种10 d后T1处理的出苗情况最好；T2处理的大豆株高、茎粗、LAI及产量表现最佳。通过统计学分析不同秸秆覆盖之间的差异，秸秆覆盖具有一定的阻碍热量传递的作用，有利于土壤含水率的提高，对大豆生长状况、光合特性及产量产生影响，0～10 cm土层秸秆还田覆盖为最佳处理。     

膜下滴灌棉田水盐运移规律研究

从不同生育期、垂直方向、水平方向对膜下滴灌水盐的运移进行分析比对发现,膜下滴灌棉花土壤含水量呈现规律性的变化。土壤含水量的变化趋势,0～20 cm土壤含水量较低,随着土层深度增加,土壤含水量逐渐增加,至30～50 cm达最大,随后又降低。膜下滴灌棉田含盐量在生育期0～60 cm土层范围内表现为积盐状态,并以30～50 cm积盐最多。此研究将为新疆棉田土壤次生盐渍化防治、膜下滴灌棉田的水盐动态监测提供理论依据。     

棉花苗床杂草防治技术

1棉花苗床杂草的发生特点在营养钵育苗田 ,由于棉花苗床钵土和盖土均取自肥沃的表土 ,杂草种子含量大 ,而苗床播种盖膜后其小气候特点是高温、高湿。据试验观察 ,苗床温度在晴天会比外界平均高出 7.4～ 1 6.0℃ ;由于播种时钵体水分充足 ,地膜覆盖后保墒效果较好 ,有利于杂草的发生 ,其发生密度可达 72 9株· m-2 ,是直播棉田的 5～ 1 0倍 ,严重影响棉苗的生长发育。棉花苗床杂草一般在播种盖膜后 6天开始出草 ,1 5天左右达到出草高峰 ;以后随着棉苗长大、外界气温升高 ,揭膜次数增加 ,土壤含水量明显下降 ,杂草出苗明显减少 ;棉花覆膜苗床…     

迟茬早稻抛秧栽培技术

早稻抛秧技术在冬闲田和绿肥、大麦等早中茬前作的应用已越来越广泛 ,而在小麦、草莓、蔬菜等迟茬前作的应用尚存疑问。为解决迟茬口早稻抛秧栽培技术 ,１９９５年以来 ,我们在浙江省临海市江南、爱国、邵家渡等乡镇开展迟茬早稻抛秧栽培探索性试验 ,在试验成功的基础上 ,加大示范推广力度 ,累计推广面积近１４００ｈｍ２ ,节本增收２００多万元 ,社会、经济效益显著。该项技术以其省工省本省力增产增收的功效在迟茬早稻中得到推广应用。一、品种选用选好前作和早稻的品种是此项技术成败的关键之一。前作是小麦的 ,宜选用熟期早 ,产量高 ,粉…     

Patterns of spatial arrangement of early potatoes

Summary Yield comparisons were made at three stages of maturity between half and whole tubers ofUlster Prince planted equidistant triangularly (row width 33 cm), and whole tubers planted at twice that row width at the same seed rates which averaged 4.5 and 9.0 tonne/ha. At the same seed rate narrow rows gave no increase in total yield at the first lift, but about 1.3 tonne/ha more at lifts made 10 and 20 days later. The higher seed rate outyielded the lower by about 4.0, 6.0 and 7.5 tonne/ha in total yield for the three lifts respectively. In yield of tubers under 32 mm, there was a large response to increased seed rate and a small response to reduced row width. Single experiments withUlster Premier andArran Pilot, showed responses which differed in some respects from those ofUlster Prince.     

早稻沼液浸种对比试验效果初报

通过对照试验,分析了沼肥对早稻秧苗素质和产量的影响。结果表明,沼液浸种能提高早稻的秧苗素质,增加总根数、白根数和总穗数,早稻产量增加9.18%。     

Etiology of potato early dying in Delaware

Greenhouse and field plot experiments along with surveys of commercial potato fields were conducted to determine the etiology of potato early dying in Delaware and its impact on yield ofSolanum tuberosum cultivar Superior.Verticillium dahliae was the primary pathogen causing early dying, and no increase in disease severity or yield loss was observed when plants were inoculated with bothV. dahliae andColletotrichum coccodes. The field survey showed thatV. dahliae was the predominant pathogen in symptomatic plants, and nematodes were not essential in association withVerticillium to cause early dying. Disease severity was the same in the presence of a low population or absence of nematodes.     

早季杂交稻新组合对比试验初报

采用单因子随机区组设计,以汕优82作对照,引进天优776等11个杂交早稻新组合在上杭县作品比试验.结果表明:天优776和安优1072分别比对照增产11.8%和10.3%,增产达极显著和显著水平,且综合性状好,可续试并扩大示范种植.     

杂交早稻新组合对比试验初报

为筛选适合莆田市荔城区种植的优质、高产、抗病的杂交早稻新组合 ,促进农业种植结构的调整 ,2 0 0 2年早季从省内外引进 4个优质杂交早稻新组合 ,安排在区良种场进行对比试验。现将试验结果初报如下 :1　试验概况1 1　参试组合与来源金优 2 0 7(湖南杂交水稻研究中心 )、夏优 82(省农科院稻麦所 )、金优 1 0 0、汕优 1 0 0 (三明市农科所 )、对照T优 7889(福建农林大学、省种子总站 )。1 2　试验地点与设置试验田位于区良种场省水稻引种观察圃内 ,乌黄泥 ,土壤肥力好 ,前作冬闲田。试验采取随机区组设计 ,3次重复 ,小区面积 1 3 34m2 ,…     

Processing potential of potato cultivars at early harvests

Summary Assessments were made in three seasons of yields and tuber dry-matter percentages at harvests from June to early August in a range of cultivars gorwn at a coastal site in south-west Wales. Lareg differences in tuber dry-matter percentage were found between cultivars within seasons and also at similar dates between seasons.The cultivar Home Guard produced consistently high dry-matter percentages each year in the period from late June to early August but cv. Redord achieved similar or higher dry-matter contents after mid-Julyl. Most other cultivars produced lower dry matter percentages throughout the sampling period. The potential for the use of early maturing cultivars in late June and July for processing into crisps is discussed.     

Nitrogen fertilizatioin of potatoes for early summer harvest

Rates of N applied to sandy loam soil with wheat as the preceding years crop was studied as to the influence on tuber yields of potatoes grown for early summer harvest in Southwestern Indiana. Most of the yield response was to the first 75 lbs/acre (84 kg/ha) increment of N which increased the yield of US #1 potatoes 61 cwt/acre in 1967 and 52 cwt/acre in 1968. The total solids were not significantly decreased by the first increment of N applied which was also the N range of rapid yield increase. N fertilization increased the N content of the foliage from 3.0 to 4.0% in 1967 and 3.97 to 5.17 in 1968 and the tubers from 1.36 to 2.96 in 1968. The first 75 lbs N increment was efficiently converted to crude protein, 48% incorporation, but the succeeding increments were poorly converted.