滇重楼种质资源抗旱综合评价及生理机制研究

水分是限制滇重楼种子休眠萌发及资源分布的重要成因。以云南滇重楼主产区6个种源地的种子为试验材料,湿度设置分别为10%（正常水分处理,CK）和3%（水分胁迫处理,T）,测定10、30和60 d时种子的可溶性蛋白（soluble protein,SP）、丙二醛(malondialdehyde,MDA)、过氧化氢酶(catalase,CAT)、过氧化物酶(peroxidase,POD)和超氧化物歧化酶(superoxide dismutase,SOD)的生理活性,对资源进行综合抗旱评价,并筛选抗旱生理指标。结果表明：随胁迫时间延长,滇重楼种子可溶性蛋白呈先下降后回升的趋势,而SOD和CAT酶活性呈先升高后降低的趋势,MDA和POD呈下降趋势。CAT活性对水分胁迫最为敏感,胁迫和对照间呈显著差异,60 d时呈极显著差异（P＜0.01）;在10 d时SOD和MDA对水分胁迫呈极显著响应（P＜0.01）,在30 d时各生理指标均受到显著影响,SOD和POD受到极显著影响（P＜0.01）。相关性分析结果显示,可溶性蛋白与SOD和POD呈显著负相关（P＜005）。滇重楼种质资源之间变异系数较大,不同种质材料对干旱胁迫的敏感性不同。综合分析,师宗、鹤庆和石林的滇重楼种源抗旱性较强,耿马地区抗旱性最弱,可为进一步抗旱基因型品种选育提供理论依据。不同评价方法对滇重楼抗旱生理指标筛选的结果较为一致,CAT、SOD和MDA可作为抗旱性鉴定的生理指标。     

油松侧柏混交林效益及种间关系的研究

对陕西省淳化县干旱阳坡立地上，１０年生人工油松侧柏混交林的研究结果表明，侧柏属浅根型树种，根系系集中分布在０～４０ｃｍ深的土层中，而油松根系在０～６０ｃｍ深的土壤中呈均匀分布。混交林的根系在土壤剖面上，垂直分布趋于均匀。行间混交林、株间混交林均能显著提高油松、侧柏的胸径、树高和材积生长量，同时能增强土壤中磷酸酶、蛋白酶和脲酶的活性，改善土壤肥力状况。尽管株间混交林能明显改善林地的土壤水分─物理性质，提高油松、侧柏的枝叶生物产量，但行间混交林在这些方面却表现出强烈的负效应。混交林对油松、侧柏针叶中的氨、磷含量的影响，随混交方式而截然不同。     

有机肥对紫色水稻土有效硅的影响

田间和盆栽试验表明，紫色水稻土施用有机肥，有效硅可提高１０％￣３５％，水生在产加６％￣１０４％，并促进了水稻植株对硅的吸收，使水稻产量提高。     

石灰性土壤中钴与磷关系的研究

采用土壤培养试验方法,通过在石灰性土壤上施用不同量的硫酸钴和磷酸二氢钾,分析研究了有效钴和速效磷含量的变化状况。初步研究结果表明:(1)土壤中有效钴和速效磷含量分别随着硫酸钴和磷酸二氢钾施用量的增加而增加;高浓度的钴磷配施下,土壤中有效钴(速效磷)含量随着磷(钴)施用量的增加而减少。(2)30天内,土壤中有效钴和速效磷含量都随时间的延续呈先增加后减少的趋势,试验结束时各处理的有效钴含量趋于一致,而速效磷含量仍在减少。(3)在土壤中钴和磷存在拮抗关系,原因可能是两者形成了低溶性的钴的磷酸盐。     

A Preliminary Study on Dynamics and Models of N, P, K Absorption for High-Yield Cotton

The field experiments were carried out to investigate the dynamics and models of N, P and K ab-sorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: Thecontents of N, P2O5, K2O in cotton leaves, stems, squares and bolls decreased obviously with the time over thewhole growth duration and the falling extent was greater in high-yield cotton than in CK. Contents of N inleaves, squares and bolls, in particular in the leaves of fruit-bearing shoot was higher in high-yield cotton thanin CK. Contents of P2O5 in squares and bolls and that of K2O in stems were higher in high-yield cotton than inCK during the whole growing period. The accumulations of N, P2O5 and K2O in the cotton plants could be de-scribed with a logistic curve equation. There was the fastest nutrient uptake at about 90 d for N, 92 d for P2O5and 85 d for K2O after emergence, respectively. Total nutrient accumulation of N, P2 O5 and K2O was 385.8,244.7 and 340.3 kg ha-1 , respectively. Approximately 12.5 kg N, 8.0 kg P2O5 and 11.1 kg K2O were neededfor producing 100 kg lint with the leaves and stems under the super high yield condition of 3 000 kg ha-1 inXinjiang.     

陕西关中塿土区线辣椒对氮、磷、钾肥的肥效反应

在陕西省关中土娄 土区布置线辣椒缺素大田试验 ,研究线辣椒对氮、磷、钾肥的肥效反应。结果表明 ,氮肥和钾肥能明显促进线辣椒的营养生长和生殖生长 ,氮肥能使线辣椒果实维生素 C含量增加 2 0 6 mg/ kg,而钾肥不仅能使线辣椒果实维生素 C含量增加 1 37mg/ kg,而且可使果实硝态氮含量降低 1 0 .3m g/ kg;氮肥可使线辣椒增产 1 9.0 % ,钾肥能增产 1 0 .4 % ,磷肥对线辣椒营养生长和生殖生长、果实品质以及产量各方面的影响甚小     

棉铃虫CYP4家族基因片段克隆及序列分析

以5龄实验室品系棉铃虫的总RNA为模板,采用一对昆虫细胞色素P450简并引物,利用反转录—多聚酶链式反应(RT-PCR)扩增并筛选出10个新的长度约450bp的cDNA片段,并对这些序列与GeneBank中已知序列进行相似性分析,初步推测这10个P450基因片段属于CYP4家族的CYP4M和CYP4S2个亚家族。     

施用磷肥对杉木幼林土壤养分和磷组分的影响

杉木［Ｃｕｎｎｉｎｇｈａｍｉａｌａｎｃｅｏｌａｔａ（Ｌａｍｂ．）Ｈｏｏｋ．］人工林土壤立地大多供Ｐ不足,杉木幼林施用磷肥肥效显著。李贻铨等认为施Ｐ、Ｋ肥能促进杉木幼林生长［１,２］;叶仲节认为幼林施Ｐ肥初期有效,施Ｎ无效,施Ｋ还会出现负效应［３］。作...     

澳大利亚昆士兰州松树杂交育种和造林

经过４０多年的努力，澳大利亚昆士兰州在松树杂交育种方面取得了举世瞩目的成绩。选育的ＰＥＥ×ＰＣＨＦ１具有母本湿地松的树干通直圆满、抗风力强、分枝习性好、耐水渍和父本洪都拉斯加勒比松的速生、皮薄等优点，除适应性广、材质好外，大面积造林比其亲本的商品材积增加３０％。文内较详细地介绍了澳大利亚昆士兰州松树杂交育种及其造林的方法     

Provenance and progeny results for the tropical white pine, Pinus chiapensis, at five and eight years of age

Eleven provenances and 132 open-pollinated families of Pinus chiapensis were established at six locations in Brazil, Colombia, and South Africa and assessed for height, volume, and forking percent at five and eight years of age. Provenance × site and family × site interactions were examined in a subset of three trials with 38 open-pollinated families in common. Average volume production of P. chiapensis in Colombia and South Africa was 25 m³/ha/yr and 12 m³/ha/yr, respectively, at eight years of age. Provenance and family differences for height and volume were significant at the individual test sites at eight years of age. The La Trinidad (Chiapas) source was the most productive. Forking percent ranged from 3% in South Africa to 38% in San Jose, Colombia at eight years. Provenance × site interactions were significant for forking but not for height and volume. Family × site interactions were significant for height and volume but not for forking. Forty-six percent of the interaction variance between height and location was contributed by only six families. Height/diameter ratios for P. chiapensis were 0.29 and 0.39 in Colombia and South Africa, respectively, and significantly different.