早春“冷害”对柑桔成花的危害

对于高温引起柑桔异常落花落果，国内已作了大量研究，而对于近二年早春出现的异常天气对柑桔成花的危害，则尚未引起足够重视。笔者试以江西长城企业集团1996年受异常天气影响导致减产为例，探讨早春“冷害”对柑桔成花的危害。1异常天气造成1996年大范围减产1996年2月中旬至4月初，我国南方出现持续低温阴雨天气，使柑桔物候期比常年延迟了一个多节气（15天以上）。据全国国营农场柑桔技术协作组统计资料，由于春季久而低温对柑桔产生了“冷害”，使我国除浙江垦区外，其他垦区柑桔都有较大幅度减产．减产幅度从大到小依次为湖南垦区、江…     

春夏异常天气对柑桔生长与结果的影响

2011年1-5月,湖北省当阳市先后出现了早春低温,春、夏持续高温干旱天气.早春的低温和春夏持续的高温干旱导致了部分柑桔园出现落叶、枝梢枯死等现象.4月上旬的低温和4月下旬的高温使柑桔的花蕾膨大受到影响,花期缩短.5月上中旬的高温干旱导致部分温州蜜柑果园生理落果加重.在春夏异常高温干旱情况下开花前及开花后叶面喷施“天达2116细胞膜稳态剂”对提高着果率有一定作用.     

冰冻灾害柑桔果园恢复生产管理技术

2008年1月中旬至2月底,我国南方柑桔产区先后出现了较大强度的低温雨雪天气,部分地区还出现了严重的冰冻天气,致使柑桔等农作物遭受不同程度的灾害,特别是四川、贵州、陕南、鄂中-鄂西、湘南-湘西、赣中等区域发生了严重的冻害。笔者参加了中国农业科学院柑桔研究所组织的由农业部岗位科学家带队的“2008年春季抗冻救灾恢复生产行动”小组,     

衢州市柑桔灾后迎增产

目前柑桔已进入定果期,2011年度浙江省衢州市柑桔生产遭受了2010年12月中旬的雪害、2011年1月中旬的低温冻害、春季干旱、5月异常低温的不利天气以及6月中旬的暴雨洪灾等自然灾害。7月中旬,衢州市组织各县、市、     

广西柑桔研究所果园历年低温天气分析

广西柑桔研究所建于1966年春,建所以来经历1969年春天一场严寒低温冰冻天气,从此连年进行冰雪与霜冻的低温天气观测,记录柑桔果园的冻害情况。现将历年的观察资料整理,供参考。1材料与方法1.1柑桔果园的基本情况广西柑桔研究所位于桂林市郊区,全所占地面积80hm2,其中果园面积60     

广西北部柑桔冻害调查

2008年1月12日至2月10日,长达近20天时间的低温阴雨天气,使广西柑桔业遭受了50年不遇的雨雪冰冻灾害,仅桂林市就有6.44万hm2柑桔受冻,造成了严重的直接和间接经济损失.关于柑桔品种田间抗寒性调查[1-2]及品种抗寒性鉴定[3-6]国内都有过报道,但对近年种植较多、发展较快的一些品种(如砂糖桔、春甜桔等)抗寒性及冻害情况未见报道.     

桂林市柑桔生产遭遇持续高温天气

本刊讯 今年果树物候延迟，5月下旬正值桂林柑桔夏梢抽发和第二次生理落果期。5月27—31日，桂林市遭遇持续5天的高温（日最高气温33℃以上）晴朗天气，促使温州蜜柑、脐橙以及桠柑等抽生夏梢能力较强的柑桔品种夏梢旺长，果梢矛盾加剧，加剧第二次生理落果。此外，持续高温干旱可直接伤害幼果，导致柑桔幼果黄化和脱落。据调查，5月高温对柑桔造成的落果加剧程度不明显，柑桔生产正常。     

2008年低温冻害对宜都市柑桔的影响

进入2008年后，湖北省宜都市出现了自1977年1月31日（极端低温-13．8℃）之后的又一次历史罕见的长期低温雨雪冰冻天气，对柑桔等经济作物越冬带来了极大影响。2月20-26日，宜都市特产技术推广中心有关技术人员在全市柑桔主产区高坝洲、五眼泉、枝城、松木坪、聂家河等乡（镇）对温州蜜柑、碰柑、柚类及定植的柑桔幼树进行了抽样调查。     

几种覆盖材料对柑桔苗防冻效果比较

近年来柑桔产区频频遭遇冰冻和倒春寒侵袭,产生不同程度冻害.特别是2008年1月,我国南方发生了50年难遇的持续低温雨雪冰冻灾害天气,造成直接经济损失1 516.5亿元,柑桔受灾面积和成灾面积居种植业第三位[1].湖北省通城县新磨良种果苗场是该县主要的林果苗木繁育基地,长期以来,在柑桔育苗过程中,冬季苗木冻害频率有不断增高的趋势,已成为苗木生产者的心腹大患.为探索经济有效的措施抵御和减轻灾害性天气对柑桔苗木生产的影响,于2008年冬及2009年冬连续2年开展了柑桔覆盖防冻技术研究.     

永福县沙糖桔避雨避寒栽培技术

沙糖桔因其果肉爽脆、汁多、化渣、味清甜,丰产性能好,而深受永福县种植户欢迎。但由于沙糖桔成熟时期一般在11月下旬～12月中旬,此时正是柑桔类其它品种集中上市时期,沙糖桔的价格优势不明显,如果推迟采摘时间,又会遇到11月末～12月连续多日的霜冻以及低温阴雨天气,造成大量受冻果、落果,商品果率严重下降。     

Effect of salinity and water table on growth and tolerance of plum and peach

The effects of combinations of salinity (no salt, 2000 p.p.m. or 4000 p.p.m. of CaCl₂ and NaCl, 1:1) and water table (30 cm, 60 cm or 90 cm from the soil surface), on the vegetative growth and tolerance of ‘Golden Japanese’ plum and ‘Mit Ghamre’ and ‘Balady’ peaches were studied. The plants were grown in lysimeters. The growth of the trunk, total shoot length, the increase in shoot length per cm and the fresh weight of top, root and total plant were reduced with increasing salinity of the irrigation water. The effect was accentuated when the plants were maintained at high water table level. The salinity treatments resulted in the death of 43%, 73% and 76% of the plants in the plum, and the ‘Mit Ghamre’ and ‘Balady’ peaches, respectively, indicating that the plum is more tolerant to salinity than the peach. The plants of the salinity treatments showed various symptoms of salt injury, such as leaf burn, defoliation, shoot die-back and finally death. In the peaches, salt injury started to occur in the first growing-season, whereas the salt injury appeared in the plum in the second growing-season. The symptoms were more pronounced in the 4000 p.p.m. treatment than in the 2000 p.p.m. treatment and were more pronounced at the high water table level. The salinity level was the predominant factor and the effect of the water table on the vegetative growth diminished with increase in the salinity level of the irrigation water.     

洞庭1号无籽西瓜套种棉花高产高效模式的研究与应用

根据西瓜、棉花两者生长发育特点进行套种试验,研究其高产高效栽培模式。试验示范结果表明,以西瓜行株距4.5m×0.65m,棉花行株距1.5m×0.45m的种植密度,西瓜与棉花之间互颉作用最小,西瓜和棉花的产量和产值在3个套种模式中位居第1,在5个处理中经济效益最高。     

Primary culture and identification of mouse PASMCs and effects of hypoxia on proliferation and apoptosis of PASMCs

AIM：To establish a fast, accurate and economical technique for culturing mouse pulmonary arteriolar smooth muscle cells (PASMCs), and to explore the effects of hypoxia on the proliferation and apoptosis of the PASMCs. METHODS：In sterile condition, the pulmonary artery was isolated from the male BALB/c mice by digesting with collagenase I, and the cells were cultured in fetal bovine serum-coated flask. Centrifugal procedure was not used during the cell passage. The cell morphology was observed under an inverted phase-contrast microscope. α-Smooth muscle actin was identified by immunocytochemistry and immunofluorescence. The effects of hypoxia on the proliferation and apoptosis of the PASMCs were detected by CCK-8 assay and TUNEL assay. RESULTS：PASMCs were identified by the methods of immunocytochemistry, immunofluorescence staining and observation of morphology. Unlike the rat PASMCs with typical subcultured peak-vally pattern, the mouse PASMCs showed a lot different without a peak-vally pattern. The cells could be subcultured after 5 d to 7 d and there was 3 to 5 generations depending on the activity of the cells. CCK-8 assay demonstrated that the A values of PASMCs exposed to hypoxia increased after 24 h (P＜0.05) as compared with normoxia. TUNEL result showed that the apoptotic index of the PASMCs in hypoxia decreased after 24 h (P<0.05). CONCLUSION：This technique for obtaining cultured mouse PASMCs is simple, fast, accurate and economical. The digestion time is easy to control. Hypoxia promotes the proliferation and inhibits the apoptosis of PASMCs.     

小檗碱和壳聚糖抗蔬菜病原真菌活性测定及复合膜制备

研究了小檗碱和壳聚糖对几种常见蔬菜病原真菌的抑制活性,以及以小檗碱和壳聚糖为主料制备复合膜的方法,并测定了该膜的药物释放效果。试验表明:低浓度(0.234 mg/mL)小檗碱即可抑制辣椒炭疽病菌(Vermicularia capsici)等5种蔬菜病原真菌的生长。20 mg/mL浓度壳聚糖对番茄灰霉病菌(Botrytis cinerea)的抑制率高达65%,而对其余4种果蔬病原真菌也有一定的抑制作用。为了集成这2种天然化合物的优点,制备了小檗碱-壳聚糖复合膜,该膜具有缓释功能,在模拟外部环境(磷酸缓冲液,pH 6.8)条件下,20 d小檗碱累计释放率接近25%,提示其在果蔬贮藏抗菌中的应用价值。     

西瓜与粮油菜套种栽培试验

近年来,我省西瓜发展速度较快,到2004年全省西瓜栽培面积已达3万hm^2.由于我省耕地面积有限,大幅度扩大西瓜单种面积,不仅造成我省西瓜与粮油菜争地的矛盾,而且土地也未能得到充分有效的利用.为了解决这一生产中存在的实际问题,我们从2002年开始,进行了西瓜与粮油菜套种的栽培试验.历经4年的试验、示范,取得了显著的经济效益和社会效益.现将试验结果报告如下.     

世界及中国鳄梨产销概况与展望

依据联合国粮食及农业组织(FAO)数据库、联合国商品贸易统计数据库(UN Comtrade)中的数据,围绕鳄梨种植面积、产量、迚出口市场、主产国生产情况、主要迚出口国贸易情况等斱面,对世界及中国鳄梨的生产与贸易迚行回顾、分析与展望,幵在此基础上,对中国鳄梨产业的发展提出建议。     

Storability of onion seeds and effects of packaging and storage conditions on viability and vigour

Fresh onion seeds desiccated to 6.0% seed moisture content (SMC) were stored in various packaging materials under different storage conditions. Seeds packed in aluminum-laminated pouches beside those stored with silica gel at 25 °C maintained satisfactory germinability and vigour after 12 months. Desiccated seeds stored in moisture impervious containers produced more vigourous seedlings. Germination potential of onion seeds increased with reduced SMC besides storage in moisture impervious packets along with desiccants as physiological and biochemical attributes are regulated. Seed viability and vigour decreased with accelerated ageing due to increased lipid peroxidation, decreased activities of several free radical and peroxide scavenging enzymes. Electrical conductance of seed leachates also increased with ageing. Thus, adoption of appropriate storage temperature and moisture control techniques would significantly affect onion seed quality, which was due to minimum accumulation of free peroxide radicals and enhanced activity of free radical scavenging enzymes.     

热处理对果蔬采后品质及病虫害的影响

采后热处理是近年来快速发展的果蔬采后处理技术,广泛应用于改善果蔬贮藏期间的品质、增强抗逆性等 方面。从果蔬贮藏期间的生理生化、采后品质及防治病虫害等方面阐述了热处理的机理,讨论了热处理对果蔬衰老 方面的生理特征如色泽、风味、硬度(软化)、失重、呼吸、乙烯释放、酶活性等变化及与抗逆性有关的诱导蛋白质合成 及基因表达的影响,较全面阐述了热处理防治果蔬贮藏期间病虫害的机理如直接作用于病菌、害虫与提高果蔬的抗 病虫性等。     

陕西冬枣黑斑病和炭疽病病原菌的分离鉴定及特征比较

以大荔县冬枣种植区采集的发病枣果为试材,采用常规组织分离法进行病原菌的分离纯化,通过柯赫氏证病法则、形态学观察及分子生物学分析,研究鉴定了冬枣黑斑病和炭疽病的病原菌种类,并采用田间调查法对2种病害为害特征进行比较分析,以期为田间有效区分冬枣黑斑病和炭疽病为害症状,并快速判断其病原类型,及进一步深入开展精准防控提供参考和指导.结果表明:陕西大荔冬枣黑斑病的病原菌为细极链格孢(Alternaria tenuissima),炭疽病的病原菌为胶孢炭疽菌(Colletotrichum gloeosporioides).2种病害均主要为害枣果实,在枣果果腰或果肩上形成黑褐色病斑,可能同时存在且症状相近极易混淆,但在病斑表面、皮下及久置表型3个方面存在明显区别.     

钾肥在小白菜和萝卜上的施用效果

采用盆栽试验方法研究了施用钾肥对小白菜、萝卜生长发育、产量、品质及钾素含量的影响。结果表明 ,施用钾肥对小白菜和水萝卜的株高、叶片数无显著的影响 ,但可提高水萝卜块根的产量 ,提高幅度为 31.0 4 %～ 97.93%。施用钾肥可提高小白菜和萝卜的蛋白质和VC含量 ,降低硝酸盐含量 ,增加植株的钾素含量