It is well known that crop monoculture can induce negative effects on soil ecosystems and crop productivity. However, little is known about how vegetable monoculture affects the soil nematode community structure and its relationship with vegetable yields. In this study, the composition, abundance, metabolic footprint, and ecological indices of soil nematodes are investigated in monocultures of pumpkin and melon. The relationships between nematode community structure and yields of pumpkin and melon were analyzed by linear regression. Both monoculture soils of pumpkin and melon suppressed the relative abundance of bacterivores but increased the relative abundance of plant parasites. Pumpkin monoculture soils decreased soil nematode diversity but increased the maturity index of plant parasites. Monoculture soils of pumpkin and melon decreased the metabolic footprint of lower- and higher-level trophic groups of the soil food web, respectively. Pumpkin and melon monoculture soils increased the food web indices channel index (CI) but decreased the enrichment index (EI) and the structure index (SI). The monoculture soils of pumpkin and melon led to a more fungal-dominated decomposition pathway and degraded soil food web conditions. The abundance of bacterivores and food web indices EI and SI were positively correlated with soil nutrients and pH, while the abundance of plant parasites and CI were negatively correlated with soil nutrients and pH. Paratylenchus was negatively correlated with pumpkin and melon yields and could be the potential plant parasites threatening pumpkin and melon productions. Redundancy analysis showed that monocultures of pumpkin and melon altered the soil nematode community via soil properties; total N, total P, alkeline-N, and pH were the main driving factors.

贵族1号是以N-15-18为母本、N-15-20为父本育成的肉用南瓜一代杂交新品种.该品种属中熟品种,黑龙江省春季露地栽培条件下,从出苗到采收生育期75 d,全生育期82 d.果实长棒状,果顶和果蒂端略细,中部略粗,果形略弯;果皮灰色,浅灰色果线,果表光滑;果肉鲜黄,果肉厚2.0 cm,粉质细腻,口感甜糯;干物质含量(w,后同)≥18％,坐果能力强,单株结瓜2～4个,单瓜质量2.2～2.5 kg,中抗白粉病、霜霉病.适合在东北地区及我国各地露地栽培,667 m2产量3200 kg左右.

黑龙江省板栗南瓜种植区域分布广泛,种植面积大,除满足本地消费市场外,作为北菜南运重要蔬菜品种大量销往全国.生产中存在化肥和农药泛滥使用,超标使用现象普遍,导致肥料利用率低、土壤、环境恶化.为了农产品的安全生产,人民的身体健康,化肥、化学农药的减施势在必行.技术以黑龙江省寒区主栽的南瓜为研究对象,依据南瓜养分需求特性与限量标准,筛选与优化化学肥料减施与替代技术.重点开展南瓜病虫害的化学农药减量使用技术研究与示范;开发利用GC-16系列生态制剂应用技术与精准施药技术,生物农药与高效低毒低残留化学农药联合应用防治病虫害的农药减量施用技术,有效控制露地南瓜病虫害的发生与危害.

'Longlv No.1'is a new cucumber F1 hybrid developed by crossing inbred line 96452 as female parent and inbred line 0104 as male parent.The plant has strong growth vigor.The fruits grow on the main vine.The fruit is about 35 cm in length with early maturity.The fruit is straight,sweet and crispy,and has dark green skin with few white spines.It is highly resistant to downy mildew,resistant to fusarium wilt and powdery mildew.It is suitable for greenhouse cultivation in winter and spring and planting under big plastic shed in spring.

"黄冠2号"是由自交系332和自交系207配制而成的油亮型旱黄瓜一代杂种,该品种早熟,植株长势较强,以主蔓结瓜为主,春季雌花节率50％以上.瓜长约19 cm,皮色浅绿、油亮,白刺稀少,果肉浅绿,商品性好.商品瓜中维生素C含量150 mg·kg-1,可溶性固形物含量3.86％,干物质含量4.08/％.每667 m2产量约4 000 kg.适宜在东北及内蒙古地区保护地栽培.

国品天香是黑龙江省农业科学院园艺分院育成的肉用南瓜新一代杂交品种.亲本为N-14-5(母本)和N-14-20(父本).该品种早熟,春季露地栽培,从出苗到采收生育期72 d,果实扁圆形,绿色,果肉浓黄,果肉厚度2.1 cm,粉质细腻;绿色条带,果实表面光滑靓丽.干物质质量分数≥20％.坐果能力强,单株结瓜2～4个,单瓜质量2.1 kg.中抗白粉病、霜霉病,耐贮、耐运.适合在东北地区及我国各地露地栽培,667 m2产量3000 kg.

'龙甜6号'是黑龙江省农业科学院园艺分院以'T-33-18'为母本'、T-28-16'为父本育成的薄皮甜瓜杂交1代新品种.该品种早熟,生育期65 d左右;果实长圆形,黄白皮,尾绿晕,转色速度快,白瓤,沙脆,单瓜质量0.45 kg.连续坐果能力强,单株结瓜5～7个,整齐一致,商品性突出,叶片肥大,生长速度快,采收期集中.667 m2产量2500 kg.适合在东北地区及我国各地区露地、棚室栽培.2019年通过中华人民共和国农业农村部非主要农作物品种登记.

龙园黄冠是由自交系216和自交系45配制而成的油亮型旱黄瓜一代杂种,早熟,植株长势中等,以主蔓结瓜为主,春季雌花节率50％以上.瓜长20cm左右,皮色浅绿、油亮,白刺稀少,果肉浅绿,商品瓜率高.田间对枯萎病、霜霉病、白粉病的抗性优于对照龙园绿春.适宜保护地种植,每667 m2产量4 000 kg左右,露地也可种植.适宜在东北及内蒙古地区栽培.

'Shengqiu No.1' is a new cucumber F1 hybrid developed by crossing 2 inbred line T1-3 and L25-7.The plant has strong growth vigor.The fruits grow both in main and branch vines.The fruit is about 18 cm in length with light green skin and few white spines.The fruit is straight with sweet and crispy pulp.It is highly resistant to Fusarium wilt,resistant to downy mildew,powdery mildew,anthrax mildew.Its average yield is 30 t·hm-2.It is suitable for cultivation in open field in summer and autumn.

'Longzao No.1' is a new cucumber F1 hybrid developed by crossing inbred line 'H1121' as female parent and inbred line '12-9' as male parent.The plant is gynecious with medium growth vigor and of early maturity.The fruit is about 22 cm in length.The fruit is of straight shape,and tastes sweet and crispy.It has light green peel with a few white spines.It is tolerant to low temperature and weak light.It is high resistant to Fusarium wilt,resistant to angular leaf spot and target leaf spot.Its yield is about 45 t·hm-2.It is suitable for protected cultivation in spring in Heilongjiang Province.

According to the debate about misusing hormone in cucumber production,the experiment treated cucumber with different concentration of Megestrol acetate and 5 kinds of hormones. The results showed that there were no changes found in flower and fruit under Megestrol acetate. And 2,4-D delayed the flowering and kept flower blooming. There was faster fruit growth ratio under GA(100 mg·L-1) treatment. Furthermore,corollas were not completely expanded under NAA treatment. However,there were improvement on fruit setting and fruit expansion under chlorine pyrazole urea and chlorobenzene oxygen ethanoic acid sodium. The effectiveness of suitable hormone concentration on cucumber fruit growth is in following order:chlorine pyrazole urea>chlorobenzene oxygen ethanoic acid sodium>2,4-D>NAA>GA>pure water(the contrast). Among them, chlorine pyrazole urea(10 mg·L-1)dipping treatment had the best effect on cucumber fruit growth,and its hormone residue detection was in compliance with EU standard(0.01 mg·kg-1).

以黄瓜为试材,以10 mg·L-1氯吡脲和100 mg·L-1对氯苯氧乙酸钠为处理对3种类型的黄瓜进行蘸花试验,对比分析了氯吡脲和对氯苯氧乙酸钠对黄瓜果实生长的影响.结果表明:氯吡脲和对氯苯氧乙酸钠处理不同类型黄瓜果实,其长度、直径、质量增长率基本一致;2种激素处理“龙早1号”黄瓜不同花期的果实,其果实的直径、质量增长率的顺序是开花前1 d＞开花当天＞开花后1 d;用氯吡脲和对氯苯氧乙酸钠处理的黄瓜果实中可溶性固形物、维生素C、干物质的含量均大于对照,且氯吡脲处理与对照相比差异显著.

海南省是我国第二大热带岛屿,也是我国最大的天然温室,生产反季瓜菜有着得天独厚的优越条件[1],但因其地处热带,病虫害发生相对较重,加上缺少系统的无公害生产技术,为了保证产量和效益,农民过量使用农药,严重降低了西瓜品质和经济效益. 黑龙江省地处高纬地带,病虫害相对较轻,生产无公害西瓜和无病虫菌残留的西瓜种子有着优越的天然条件.于是,将北方生产的西瓜种子冬季在海南进行反季生产,既可以满足冬季到海南猫冬的“候鸟”吃上北方的特色西瓜,又能改善海南西瓜的质量,同时还可以使北方的特色小西瓜打入海南市场.

种子纯度在种子生产中的地位日益提高，以往的形态鉴定等方法难以满足种子强度鉴定的要求，因而分子标记技术越来越多地被应用到种子纯度鉴定中。文章介绍了 SRAP 分子标记技术的基木原理和特点，简要论述SRAP 标记技术在农作物种子纯度鉴定上的研究进展。

导读：近年来黄瓜枯萎病发生严重，田间发病率在10%～30%。保护地黄瓜受害更重，经常造成全株枯死，乃至减产或绝产，这大大削弱了农民种植黄瓜的积极性。所以在生产上应提早预防，综合防治，从根本上减轻黄瓜枯萎病的发生。本文根据多年生产经验，从种子处理到苗期及定植后田间管理，以及发病后的防治，阐述一些防治措施，以供广大种植者参考。

Pathogenicity determination of fusarium wilt pathogens in cucumber preservation in icebox for 11-22 years since 1984 was studied. The results showed that pathogens preservation for 22 years in PDA solid slant medium in test tube were still high pathogenicity. Preserved by the same method and different period,difference between survival rate of bacterial strain and pathogenicity was not significant. Preserved by the same period and different method,difference was significant. The method of PDA solid slant medium and wheat grain in trigonal tank were better.

Processing cucumber Jinchun is a new F1 hybrid using inbred line H141 as female parent and L25-7 as male parent.Plant vigour is medium.The character of early mature was very good.The fruit was short-cylindrica shape,green color of fruit peel and few white spine.Shape index of fruit was about 3.5.Commercial value,high yield and disease resistance are all outstanding.It is suitable for storage,processing and fresh-eating,cultivation in spring openground.

Little Picking Cucumber is a sort of special vegetable,mastering the cultivation techniques may increase its planting area and enlarge its economic benefit.