不同负载量对‘蜂糖李’产量和果实品质的影响

为提高‘蜂糖李’产量,改善果实品质。本研究以9年生‘蜂糖李’为试材,研究了4个负载量水平,即201~400个果实/株(T1）、401~600个/株（T2）、601~800个/株（T3）和800个/株以上（T4）对其产量和果实品质的影响。结果表明,随着负载量的增多,产量随之增加,而单果重和果实品质则降低。其中单株负载量在601~800个,果实的整齐度最佳,产量为27.76kg/株,显著高于T1和T2;T3可溶性固形物含量高达19.63%,糖酸比44.98,维生素C含量为3.32 mg?(100g﹣1),产量和品质表现良好。合理的负载量能提高‘蜂糖李’的产量和品质,单株控果量在601~800个间最适宜。     

平欧杂交大果榛子高产栽培技术

大果杂交榛子,属桦木科榛属植物。其果实（坚果）个大、皮薄、单果重2-2.5克,出仁率高,风味优于欧榛;产量高,盛果期单株产量可达2公斤左右,平均亩产可达100-125公斤,高产可达150公斤以上,且能抗-30℃-32℃低温,我国北方寒冷地区可栽植。     

今年湖北早桃货丰价宜

受去年冷冬和今春花期气候温和少雨的下面影响,湖北早桃今年各大桃区均是丰产的大年。据笔者近期从该省枣阳、随州、孝感及东西湖几大桃区销售形势来看,今年的情况不及去年好。特早熟品种春花、早霞露因果实膨大期干旱无雨和挂果偏多的影响,果个偏小（单果重普遍在８０ｇ以下）,售价较去年低０．２０元／ｋｇ（去年为 １．６０～２元／ｋｇ）,而且销售仍不畅。随后上市的玫瑰露、金华大白桃,因果实膨大的后期遇雨,果个明显大一些,售价则较高,每公斤在ｌ．６０元以上。早熟品种砂子早生、安农水蜜等品种,因着果率不高、挂果适中,…     

钙镁配施对琯溪蜜柚果实产量和品质及钙镁养分的影响

为探究钙镁配施对琯溪蜜柚果实产量品质及钙镁养分的影响,以福建平和15年树龄酸柚砧白肉琯溪蜜柚为试验材料,设置钙肥（CaO）、镁肥（MgO）施用总量为1.50 kg/株,而钙、镁配比不同（ 0:0,9:1,8:2,7:3,6:4）的5个处理,连续进行2年（2017-2018年）的试验。结果表明,琯溪蜜柚叶片Ca含量在果实生长期呈逐渐上升的变化规律,果实成熟期达最大值,叶片Mg含量的变化趋势与Ca相反,在果实膨大期出现最低值;连续钙镁配施既能保证果实对Ca、Mg的吸收,又能缓解叶片缺乏Ca、Mg。增加钙肥比例显著降低果实可滴定酸,提高固酸比、Vc和出汁率,而增加镁肥比例显著降低果实可溶性固形物,但提高果实Vc含量、可食率和出汁率。综合果实产量品质等指标,推荐成年白肉琯溪蜜柚钙肥（CaO）、镁肥（MgO）施用量分别为1.05 ~1.27 kg/株和0.15~0.33 kg/株。     

冬春季异常天气对枇杷生长发育影响

本试验筛选出连阴雨年份（2018～2019）、“暖冬”年份（2019～2020）以及未出现上述异常天气的对照（ck）年份（2017～2018）3个枇杷花果期发育年份,将各年份枇杷发育期,果实产量、品质数据等观测指标分析：（1）冬季连阴雨年份花期缩短,但由于该年度未有低于-3℃冻害影响,对后期果实膨大幼果生长发育等关键生育期均无明显影响;暖冬年份春芽开放期较对照年份提前了两周左右,果实成熟期较上两个年度提前了5～6d,其它发育期受非冻害的冬春季异常天气影响不明显;（2）暖冬和连阴雨年份等冬春季非冻害异常天气,对枇杷产量影响较少,甚至还带来一定程度增产,侧面反映冬春季制约枇杷产量的主要因素还是冻害;（3）从果实生长曲线和果实品质对比发现,果实的膨大和果实品质的产生主要受4月之后的天气条件影响,前期的异常天气对膨大后果实发育和果实品质影响有限。故在保证花期不受冻害的条件下,重点调控果实进入迅速膨大期后的4～5月份温、湿、光照等气象要素条件,有助于调控果实品质。     

不同的栽植密度对大果甜杨桃果实产量及品质的影响

摘 要：研究不同栽植密度对广西农科院园艺研究所自主选育的大果甜杨桃1号、大果甜杨桃3号果实产量及品质的影响,旨在选择最合适大果甜杨桃栽培的密度,为生产高产优质的大果甜杨桃、完善甜杨桃相关高效栽培技术提供理论依据。试验采用4组不同的栽植密度（22株/667m2、44株/667m2、88株/667m2、176株/667m2）处理,连续测定第3年、第4年、第5年果树的产量及果实品质生理指标。研究结果表明：不同的栽植密度对大果甜杨桃果实产量的影响差异显著,当栽植密度为88株/667m2时,5年生杨桃树产量达到最大且高于其他处理组;而果实品质指标与22株/667m2、44株/667m2的2个栽植密度间差异不显著。对栽植密度为176株/667m2的4年生杨桃树间伐至栽植密度88株/667m2,栽培的第5年杨桃果实产量明显提高,但仍然低于最初按照88株/667m2密度栽培的产量。结论：4种密度试验中,大果甜杨桃栽植密度为88株/667m2时产量最高,果实品质好,经济效益最大为最佳栽植密度,可在生产上广泛应用推广。     

疏果对中桃红玉果实品质、产量的影响及效益分析

摘要：以4年生中桃红玉丰产树为试验对象,设每株不同留果量（40个果、60个果、80个果、100个果）4个处理,以不疏果为对照,连续3年研究疏果对中桃红玉产量、果实品质及经济效益的影响。结果表明,疏果提高了单果质量、优质果率、可溶性固形物含量较对照提高了1～2 %,显著提高了果实品质与产量,有效解决了中桃红玉果实整齐度不高、优质果率低的问题,每667m2 可增收1000 元以上。     

源东白桃标准化生产初探

1　标准化生产的概念　所谓“标准化生产” ,即确定发展源东白桃有明确的生产方向。它包括生产方向、市场目标、产品规格及相应的技术目标和要求等4个要素。2　果品质量标准化　果品质量是一个综合性状 ,最主要的是美观和可口 ,并反映在果实外形、大小、着色度、风味、香气、硬度和质地等方面。2 1　大小和形态　源东白桃果实广卵圆至圆形 ,主要由黄肉桃连黄的基因遗传来决定 ,同时也受个体发育、栽培条件的影响。果实大小也在一定范围内有较大变化。该品种在原产地初结果树 ,最大单果重 15 0～ 2 0 0ｇ ,北移后能达 30 0～ 35 0ｇ。从商品…     

日本桃树新品种介绍

作者 1996年赴日留学期间对日本桃树品种选育作了考察。现就日本桃主产区推广的新品种简介如下 ,供引种时参考。1　长果 1号　由长野县果树试验场育种部用川中岛白桃和八千姬杂交而成。单果重 2 50ｇ左右 ,品质优于白凤 ,在日本冈山 7月上旬成熟 ,无花粉 ,需人工授粉。2　长果 6号　由长野县果树试验场用川中岛白桃和晓杂交育成。单果重 30 0ｇ以上 ,很少双胚果和核裂果 ,成熟期介于川中岛和白凤之间 ,产量稳定。3　御坂妃子　山梨县东八代郡御坂町的小岛傅氏发现的浅间白桃枝变品种 ,1997年 7月品种登录。花后 141～ 145天果实成熟 ,属晚熟…     

百香果果实在不同栽培区域的性状表现

通过分析比较来自三个不同种植栽培区域不同品种的百香果果实,研究了其纵径、横径、单果重及可溶性糖含量等性状表达对在不同栽培区域环境的响应效果表现。结果表明,大黄金在大田镇露地种植的果实表现最优,果实纵径、横径、单果重和可溶性糖含量均最大,其中平均单果重达116.5g,可溶性糖含量达17.1%;满天星在细水乡种植地的果实性状最佳,果实纵径、横径、单果重均最大,可溶性糖含量较高（15.8%）。不同区域的小黄金和台农果实性状表达差异较大：小黄金在大田镇露地种植的果实纵径、横径和单果重均最大,而可溶性糖含量（16.7%）极显著小于两院种植的果实（18.0%）。台农在细水乡种植的果实性状表达显著优于其他种植区域,果实纵径、横径、单果重和可食率均显著或极显著高于另外2个种植栽培区域的果实,可溶性糖含量最高（17.7%）。综上,这三个区域反季节种植的大黄金和满天星果实综合表现较优,小黄金和台农稍差些。     

Spatial visualization of progressive states of maturing lentivirus.

Progressive states of maturing lentivirus: maedia visna virus (MVV) and human immunodeficiency virus (HIV), respectively, have been visualized by 2-D electron microscopy and by 3-D electron microscopic tomography. A major fraction of MVV and a low percentage of HIV appear as immature particles 4 to 5 days post virus infection. Upon budding the gag-precursor material is densely packed inside the external envelope. After virus release the major portion of precursors is assembled within an approximately 25 nm thick layer directly attached to the envelope. Structural maturation of the core is different for the two viruses. Pleomorphic cores are observed in mature MVV in contrast to structurally defined cores of HIV. The latter are principally cone-shaped, spanning the entire diameter of the virion with a 40 to 60 nm wide free end and an approximately 20 nm narrow end attached to the envelope with a core-envelope-link.     

Oestrogen concentration in the peripheral plasma of maturing pullets

The concentrations of total steroid oestrogen, measured as oestradiol‐17β, in the peripheral plasma of four maturing pullets were determined by radioimmunoassay. The concentrations fluctuated but showed an overall increase to reach maximum values some 2 to 3 weeks before the first egg was laid.     

早熟梨综合管理技术要点

古泉镇是宣城市宣州区“早熟梨之乡”,其早熟梨因石细胞少、汁多化渣等特点深受消费者欢迎,早在2004年5月,经过注册的“古泉”牌早熟梨就顺利通过了农业部无公害农产品质量认证,现已成为该镇主导产业之一。笔者经过多年探索,总结出—套丰产优质栽培技术,以供参考。     

葡萄三膜覆盖早熟促成栽培技术

葡萄三膜覆盖的早熟促成栽培技术,充分利用了早春的光热资源,起到了前期增温、保温与后期的促进着色和避雨等作用,在浙江应用葡萄三膜覆盖,具有防早春低温冻害、避开7、8月台风减轻危害、提早葡萄成熟的效果,本文对葡萄三膜覆盖促成栽培技术及效果进行了总结。     

An analysis of body weights and maturing patterns in western range ewes

The objectives were to determine the association of maturing patterns with growth rates and body weights and to estimate heritabilities and genetic and phenotypic correlations among these characters of sheep. Records of 1,109 range ewes from the Montana Agricultural Experiment Station Red Bluff Research Ranch at Norris were analyzed. Body weight and degree of maturity of body weight at birth, weaning, 12 mo of age, 18 mo of age and maturity (body weight only), and absolute growth rate (AGR), absolute maturing rate (AMR) and relative growth rate (RGR) over various age intervals were examined. Mature weight, required to calculate degree of maturity and AMR, was estimated by the average of the fall weights taken at 42, 54, 66 and 78 mo of age. Heritability estimates were .53 +/- .12 for mature weight and from .26 to .46 for immature weights. Genetic correlations among body weights at all ages were positive and generally large between immature weights and mature weights. Heritability estimates for degree of maturity ranged from .63 +/- .12 at 12 mo of age to .19 +/- .11 at 30 mo of age, at which time maturity was being approached. Genetic correlations between degree of maturity and body weight at the same age were positive; however, degree of maturity at all ages was negatively correlated with mature weight. Animals more mature at any age or stage during growth tended to be more mature at later stages, to be lighter at maturity, and to grow faster and weigh more up to 12 mo of age. Heritability estimates for AGR, RGR and AMR were moderate to high and were similar for the same age intervals. Selection for any one of the measures of growth rate would tend to expand the shape of the growth curve toward heavier weights and lower degree of maturity for any interval.     

甘肃陇中地区中熟早熟青贮玉米品种生产性能研究

【目的】筛选生产性能高、适宜于作为秋播小黑麦复种青贮玉米作物的品种。【方法】研究 9 个中熟早熟青贮玉米品种（华美 2 号,利合 228,利单 656,大京九 26,京科青贮 932,武科青贮 107,西蒙青贮 707,豫青贮 23,蒙青贮 1812）在甘肃中部地区的农艺性状和草产量。【结果】豫青贮 23 的株高、穗位高和叶片数均表现较好,生长发育较快,2020 和 2021 年的鲜草产量均最高,分别为 140. 95、79. 13 t/hm² ,达到了青贮玉米的最佳收获期;西蒙青贮 707 虽叶片数量较少、株高低、叶片较短较宽,但穗上叶数量较多 、茎秆较粗,2020 年鲜草产量较高,为 115. 4 t/hm² ,2021 年由于干旱,鲜草产量仅为 56. 6 t/hm² ,两年均达到了青贮玉米的最佳收获期。【结论】综合分析参试品种的草产量和生育时期,豫青贮 23 和西蒙青贮 707 适宜在甘肃中部地区种植,可作为秋播小黑麦的复种作物。     

农业装备在早熟温州蜜柑宫川延后采收栽培上应用

利用大棚、银黑双面反光地膜、微滴灌系统等农业装备栽培早熟温州蜜柑宫川,规避柑桔寒害、冻害,调控土壤水分,提高光照效率,延后柑桔采收期至农历春节期间,柑桔不仅品质好,而且新鲜,经济效益十分可观。     

Expression of small stress protein hsp20 gene in the maturing rat testis

In this study, we cloned a cDNA that encodes a small heat shock protein, Hsp20 (alphaB crystallin-related protein), from a maturing rat testis by means of differential display. The full-length cDNA sequence was completely identical to that registered in the DNA databank. The expression of Hsp20 gene was detected strongly in the heart and slightly in the testis of a 9-week-old rat. The expression of Hsp20 increased gradually from three weeks to 9 weeks, and the strongest expression was observed in the testis at week fifteen. The expression was localized in spermatocytes and round spermatids. The gene expression was not affected by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) when it was administered into male rats during the nursling period.