Selection for fall dormancy (FD) in alfalfa can impact other traits, such as dry matter yield (DMY), winter survival rate (WSR) and chemical compositions. Nine alfalfa varieties were mowed during the early flowering stage from 2015 to 2018. The results showed that the WSRs of both Zhongmu No. 2 and Caoyuan No. 3 exceeded 95% and there was a significant negative correlation between the FD rating and WSR (-0.988; P less than 0.01). The four-year average DMY of Zhongmu No. 2 was the highest (11,912 kg ha-1). The crude protein contents of Caoyuan No. 3 and Zhongmu No. 2 were both greater than 20%. Zhongmu No. 2 had the lowest acid detergent fiber (30.2%) and neutral detergent fiber (48.4%) contents as well as the highest relative feed values (126). Zhongmu No. 2, Adrenalin, Gold Empress and Caoyuan No. 3 (FD 1-4) were the optimum alfalfa varieties for planting in Hohhot, Inner Mongolia, China.

筛选适宜呼和浩特地区种植的苜蓿品种,探讨苜蓿秋眠等级与生产性能及越冬的关系,为建植苜蓿人工草地提供优良品种.收集国内外8个不同秋眠等级紫花苜蓿品种进行试验,采用随机区组设计,于2015-2017年每年初花期进行刈割,调查越冬率,测定株高、再生性、茎叶比、干草产量及营养成分[粗蛋白质(crude protein,CP)、干物质(dry matter,DM)、酸性洗涤纤维(acid detergent fiber,ADF)、中性洗涤纤维(neutral detergent fiber,NDF)]含量,计算相对饲用价值(relative feed value,RFV),通过相关性分析和隶属函数评价筛选出最优苜蓿品种.结果表明,中苜2号、草原3号和驯鹿苜蓿越冬率(>95％)与金皇后苜蓿差异不显著(P>0.05),但显著高于与其他苜蓿品种(P<0.05).秋眠等级与越冬率存在极显著负相关关系(P<0.01),相关系数为-0.984,而秋眠等级与苜蓿干草产量相关性不显著(P>0.05).2015年,秋眠型苜蓿中苜2号干草产量最高,显著高于其他苜蓿材料(P<0.05);2016年,中苜2号和金皇后苜蓿干草产量较高,二者显著高于其他苜蓿品种(P<0.05),而WL525和驯鹿苜蓿干草产量较低;2017年,中苜2号苜蓿干草产量最高,其次是金皇后和草原3号,以上3个苜蓿品种显著高于其他苜蓿品种(P<0.05).通过3年试验发现,中苜2号苜蓿的干草产量和相对饲用价值均为最高,酸性洗涤纤维、中性洗涤纤维含量最低,苜蓿纤维含量越低,饲用价值越好.草原3号、中苜2号苜蓿的粗蛋白含量均大于20％,粗蛋白含量越高,营养价值越好.运用隶属函数综合评价,确定中苜2号、金皇后和草原3号属于最佳苜蓿品种.苜蓿秋眠等级与越冬率呈显著的负相关关系,秋眠等级对苜蓿干草产量、营养成分等生产性能无显著影响.中苜2号、金皇后和草原3号苜蓿品种在3年干草产量、越冬性及营养品质方面均表现较好,较适宜呼和浩特地区种植.

苜蓿产量高、品质优,具有较强的抗逆性、适应性和再生能力,是畜牧生产中必不可少的优质饲草.苜蓿历经上千年的进化,具有丰富的种质资源,种质资源研究对品种多样性、品种改良和培育具有重要的意义.近年来,有关苜蓿种质资源的研究有了较大的进展,新品种不断被培育出来,转录因子、功能性基因逐渐被挖掘.笔者从遗传多样性、农艺性状、抗逆性以及基因组等方面系统地阐述了苜蓿种质资源评价工作,以期为苜蓿种质资源挖掘和鉴定奠定基础,为高产、优质、抗性育种提供参考.

为了研究60Co-γ辐射对谷稗幼苗抗盐碱生理特性及抗氧化酶活性的影响,试验选择经不同剂量(50,100,150,200,250 Gy)60Co-γ辐射处理的谷稗种子为材料,经NaCl和NaHCO3胁迫半致死浓度筛选后对其幼苗进行胁迫处理,测定叶片的可溶性糖、可溶性蛋白、脯氨酸等生理特性指标和过氧化物酶(POD)、过氧化氢酶(CAT)等抗氧化酶活性的变化,并采用隶属函数法对各辐射剂量谷稗幼苗叶片的耐盐碱性进行综合评价.结果 表明:依据谷稗种子发芽率确定280 mmol/L的NaCl和80 mmol/L的NaHCO3为半致死浓度;半致死浓度盐碱胁迫对谷稗幼苗生理特性指标及抗氧化酶活性产生了一定的影响,经过一定剂量的60Co-γ辐射可以提高谷稗幼苗渗透调节和抗氧化的能力,150 Gy剂量的60 Co-γ辐射的种子抗逆性最强.说明在盐碱地推广谷稗人工种植时可对谷稗种子进行150 Gy剂量的60Co-γ辐射处理,能有效地提高谷稗幼苗的抗盐碱性.

[Objective]The objective of this study was to investigate the effects of fall dormancy on yield,nutritive value and winter surviving rate of different alfalfa varieties for selecting proper alfalfa varieties in Hohhot and surrounding areas.[Method]Five alfalfa varieties were selected and sowed in Helinger on May 20,2014.The growth and winter surviving rates were observed from 2015 to 2017,and dry matter (DM),crude protein (CP),acid detergent fiber (ADF) and neutral detergent fiber (NDF) were analyzed.Fresh yield,hay yield and relative feed value (RFV) were calculated.The optimal alfalfa variety was determined based on hay yield and RFV.[Result]Alfalfa varieties with lower fall dormancy levels had later returning green time in spring,while those with higher fall dormancy levels had lower winter surviving rates.The three years averaged fresh yield and hay yield of the five varieties had very significant difference (P＜0.01).The fresh yield and hay yield of Gold empress were the highest and very significantly higher than that of other varieties (P＜0.01).Caoyuan No.3 had the highest CP and RFV,but the lowest ADF and NDF.ADF and NDF of Caribou was very significant higher than other alfalfa varieties (except ADF of the Gold empress) (P＜0.01).Caoyuan No.3 and Gold empress were better than other alfalfa varieties.[Conclusion]There was significantly negative correlation between fall dormancy and winter surviving rate.The varieties of Gold empress and Caoyuan No.3 with fall dormancy levels of 1-3 had better fresh yield,hay yield,winter surviving rate and nutrition over the three years,and they were suitable for planting and promotion in Hohhot and surrounding areas.

羊草是欧亚草原主要的建群种之一,已成为我国北方建立永久性人工草地的主要草种,饲用效果好、耐牧耐践踏,兼具经济和生态价值.合理施肥是提高作物产量和品质的有效方法之一.现综述氮肥对羊草的产量、品质、种子生产及经济效益的影响,为羊草的种植提供理论基础.

采用培养皿滤纸发芽法,以公农1号紫花苜蓿和龙牧806苜蓿为试验材料,分别测定内蒙古(呼和浩特)和黑龙江(齐齐哈尔)2个地区苜蓿种子的发芽率、发芽指数和简化活力指数,比较分析不同生态环境下苜蓿种子质量差异.结果表明,在呼和浩特地区,公农1号紫花苜蓿种子发芽率(96.3％)和发芽指数(38.47)最高;龙牧806苜蓿种子简化活力指数(0.159)最大.呼和浩特地区苜蓿种子的发芽率、发芽指数及简化活力指数优于齐齐哈尔地区,不同生态环境对苜蓿种子质量影响较大.

Alfalfa (Medicago sativa) is a major forage crops throughout the world,and of great nutritional,economic,and ecological value.It is mainly cultivated in the northwestern and northeastern regions of China,where water is the main limiting factor influencing plant yield.In this study,we quantified changes in photosynthesis,respiration,antioxidant activity,osmoregulation,and abscisic acid levels under drought stress,and proposed the mechanisms of physiological response to drought stress in alfalfa.The response process involving transcription factors,protease genes,and drought-resistance genes under drought stress was investigated as well.In conclusion,our study emphasized the importance of response to drought stress in alfalfa from a new perspective.

为了分析叠氮化钠(NaN3)诱变和盐碱胁迫对苜蓿愈伤组织生长的影响,以苜蓿愈伤组织为材料,进行了不同浓度NaN3诱变和不同盐碱(NaCl、NaHCO3、Na2CO3)胁迫处理,对诱变和胁迫后愈伤组织的存活率和生物量进行了测定.结果表明:随NaN3和盐碱浓度的增加,愈伤组织的存活率降低;在NaN3浓度为3.0 mmol/L和5.0 mmol/L时,诱变8d愈伤组织的存活率分别为54.17％和8.00％,说明3.0 mmol/L和5.0 mmol/L为NaN3诱变愈伤组织的半致死浓度和致死浓度;在盐碱胁迫处理后愈伤组织生长12 d测存活率,当NaCl和NaHCO3浓度为150 mmol/L时愈伤组织的存活率为52.26％和51.52％,当Na2CO3浓度为100 mmol/L时愈伤组织的存活率为50.00％,这两种浓度为三种盐碱的半致死浓度;当NaCl、NaHCO3和Na2CO3浓度为200 mmol/L时愈伤组织存活率均低于5％,此浓度为三种盐碱的致死浓度.不同NaN3浓度明显影响愈伤组织的生长,特别是在NaN3浓度为5.0 mmol/L时对愈伤组织生物量产生了明显的抑制作用;在NaCl、NaHCO3和Na2CO3胁迫时,愈伤组织的相对生长率随盐碱胁迫浓度的增加而降低,三种盐碱浓度在200 mmol/L时,愈伤组织的相对生长率下降幅度最大,对愈伤组织相对生长率的影响效果为Na2CO3＞NaHCO3＞NaCl.

松嫩秣食豆是黑龙江省优质的饲用豆科作物新品种,为解决松嫩秣食豆的合理利用问题,笔者在松嫩平原西部地区开展了秣食豆不同刈割时期(盛花期、结荚期、成熟期)对其产量及品质的试验研究,对松嫩秣食豆的产量和品质进行综合评价.结果表明:松嫩秣食豆在黑龙江西部地区9月初结荚期刈割其鲜草产量达63 703.70 kg/hm2,相对饲用价值显著高于成熟期(P＜0.05),为产量和品质的最佳平衡点.说明松嫩秣食豆最佳刈割时期为结荚期,其利用模式适宜在东北寒冷地区及类似气候地区示范推广.

为了帮助苜蓿田经营者判断处于潜在退化危险的土地,给出潜在问题和潜在机遇的早期预警,试验对松嫩平原紫花苜蓿田土壤酶活性、土壤理化性质的动态变化进行初步评价.结果表明:在松嫩平原西部干旱地区,不同种植年限紫花苜蓿田土壤理化性质在紫花苜蓿种植第9年时是个转折点,其中土壤pH值、全磷含量、全钾含量、速效磷含量随种植年限的增加呈先升后降的趋势,其中全磷和速效磷高峰值在第6年出现,pH值和全钾均在第9年达到最高,但是全钾在第6年和第9年间差异不显著(P＞0.05),之后趋于平稳;土壤含水量、全碳含量、全氮含量、速效氮含量、速效钾含量随年份的延长整体呈先降后升的趋势,并且均在9年时达到最低,与其他各年份差异显著(P＜0.05).纤维素酶活性与可溶性氮含量呈极显著正相关(P＜0.01),而与其他理化性质不相关;转化酶与各理化性质均不相关;脲酶活性与全碳含量和速效氮含量呈极显著正相关(P＜0.01),与全钾呈显著负相关(P＜0.05);过氧化氢酶活性与土壤pH值呈显著负相关(P＜0.05),与全磷呈显著正相关(P＜0.05).说明在松嫩平原西部干旱地区紫花苜蓿种植9年时可作为评价紫花苜蓿潜在退化的临界时期.

为确定有助于提升稗草种子耐盐性的60 Co-γ射线辐射剂量,对不同浓度NaCl、NaHCO3和NaCl+NaHCO3胁迫下种子发芽率的变化进行分析,确定了3种盐碱的半致死浓度,同时对不同剂量辐射处理的种子进行3种盐碱胁迫处理,比较辐射种子在3种盐碱胁迫下种子萌发和芽苗生长的影响.结果表明,3种盐碱胁迫的半致死浓度分别为280 mmol·L-1 NaCl、80 mmol·L-1 NaHCO3和280 mmol·L-1 NaCl+70 mmol·L-1 NaHCO3;适宜辐射剂量可以促进N aC l胁迫下种子的发芽率、发芽势、发芽指数、活力指数及芽苗总长、胚芽长、根长、鲜重、干重、相对含水量和NaCl+NaHCO3胁迫下种子的发芽率、发芽指数和芽苗干重,NaHCO3胁迫抑制种子萌发和芽苗的生长,增加芽苗鲜重、干重和相对含水量.不同辐射剂量对3种盐碱胁迫种子萌发和芽苗生长各指标的影响不同,隶属函数综合分析,辐射剂量在50,100和150 Gy能提高稗草种子耐NaCl能力,但辐射不能提高其耐NaHCO3和混合盐碱能力.

In order to study the effect of 60Co-γray radiation on the growth of alfalfa seedlings and the activity of two antioxidant enzymes,the experiment was carried out with the dry seeds of ‘Longmu 806 ’as the material.The seeds were treated with different doses of 60 Co-γray radiation (600,900,1 200,1 500 and 1 800 Gy).The effects of 60Co-γ ray radiation on the germination rate of seeds,survival rate of seedling,seedling height,growth index and peroxidase and catalase activities in leaves were studied.The results showed that the germination rate and seedling survival rate of Alfalfa dry seeds after 60Co-γ ray radiation presented a downward trend with the increase of radiation dose,and the seedling rate was 0 when the radiation dose was 1 800 Gy.With the increase of radiation dosage,the length of the seedlings and the length of the stems increased first and then decreased,the length of the main roots,the fresh weight,dry weight and moisture content of the seedlings all showed a decreasing trend.The catalase activity and peroxidase activity of the seedling leaves and roots increased first and then decreased with the increase of radiation dosage.When the radiation dose was 900 Gy,the activity of the two enzymes had the maximum accumulation.

为了评价不同苜蓿种质资源在齐齐哈尔地区的表现,试验对引进的30份国内外苜蓿种质资源单株的物候期、抗寒性、茎叶性状以及单株产量进行测定、评价.结果表明:育成品种、地方品种和引进品种在物候期、抗寒性和茎、叶、单株产量性状方面存在差异.育成品种和地方品种较引进品种不仅返青早,而且单株产量性状较优.返青较早的苜蓿品种有肇东苜蓿、海拉尔黄花苜蓿和草原1号苜蓿.单株干草产量在450 9以上的有5个,分别为肇东苜蓿、龙牧801苜蓿、龙牧803苜蓿、公农1号苜蓿、甘农1号杂花苜蓿.

为了探讨CaCl2缓解聚乙二醇(PEG)胁迫下2种抗旱性不同品种苜蓿幼苗叶片解剖结构的变化,试验采用石蜡切片方法,对2种苜蓿叶片解剖结构进行观察和比较.结果表明:在PEG胁迫后苜蓿叶片厚度、上下表皮厚度、栅栏组织和海绵组织厚度、中脉厚度、栅海比值、叶片栅栏组织结构紧密度(CTR值)和叶片海绵组织结构疏松度(SR值)均有降低趋势;经CaCl2缓解后这些数据有升高趋势,其中叶片厚度、上下表皮厚度、栅栏组织和海绵组织厚度、中脉厚度等指标差异较大,栅栏组织厚度/海绵组织厚度(栅海比)、CTR值和SR值差别较小;抗旱性强的草原1号苜蓿叶片的栅栏组织较厚,叶片组织紧密度大、疏松度小,栅海比较高,中脉厚度比较大.

本文采用培养皿滤纸和脱脂棉发芽法,比较分析了秫食豆、苦荬菜和谷稗种子的发芽率和发芽指数以及不同发芽床对种子萌发的影响.结果表明,在培养皿放置脱脂棉和滤纸两种不同发芽方式下,三种饲料作物种子在脱脂棉上发芽率和发芽指数明显高于滤纸上的发芽率和发芽指数,说明脱脂棉发芽床优于滤纸发芽床.

为了明确6种草坪草(紫羊茅、高羊茅、羊茅、草地早熟禾、大青山早熟禾和少叶早熟禾)的抗旱性强弱顺序,试验在对照(30％～20％)、轻度干旱(20％ ～ 15％)、中度干旱(15％ ～ 10％)、重度干旱(10％～5％)4个水分胁迫梯度下,对6种冷季型草坪草的可溶性蛋白(SP)、丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的变化情况进行了测定.结果表明:随着干旱胁迫程度的加剧,6种草坪草的SP和MDA含量均呈现上升趋势,干旱胁迫由中度干旱改为重度干旱时MDA含量趋于下降;而随着干旱胁迫由轻度转至重度,SOD、POD和CAT活性呈现先升高后降低的变化趋势;运用隶属函数对6种草坪草抗旱性进行比较,得出抗旱性强弱次序为紫羊茅＞少叶早熟禾＞高羊茅＞草地早熟禾＞羊茅＞大青山早熟禾.

为了研究油污胁迫对紫花苜蓿种子萌发和幼苗生长的影响,以及不同浓度海藻糖(TH)对油污胁迫的缓解作用,试验以紫花苜蓿种子为材料,采用室内盆栽的方法在花盆中分别加入5,10,15,20 mmol/L的海藻糖溶液500 mL,测定苜蓿种子发芽率、发芽势、芽长、根长等指标.结果表明:油污胁迫下紫花苜蓿种子的发芽率、发芽势、幼苗的根长都呈下降趋势,而添加不同浓度的外源海藻糖对油污胁迫有明显的缓解作用,其中以20 mmoL/L的效果最好.说明海藻糖能够缓解油污对紫花苜蓿种子萌发和生长的抑制作用.

紫花苜蓿是全球公认的优质牧草,近年来在我国的发展也较为迅速.黑龙江省是全国重要的奶业大省,而饲草的生产却远远满足不了畜牧业发展的需求,尤其是能提供优质植物性蛋白的苜蓿的生产.现从政策、环境、产出等方面综述了黑龙江省苜蓿业发展的迫切性与必要性,旨在为黑龙江省苜蓿业发展提供理论基础.

为了筛选出适宜黑龙江地区种植的优质饲用高粱品种,试验在高粱孕穗期、开花期和成熟期收割,测定了饲用高粱的株高、茎粗、鲜草产量、干鲜比和干草产量.结果表明:不同饲用高粱品种生育进程存在明显差异,其中Ms1990、海牛、超卡、F10、3701、As6021、健宝、绿巨人不能够正常抽穗开花,在当地不能成熟.对饲用高粱鲜草产量进行测定,鲜草产量以Ms1990最高,为962 80.42 kg/hm2;帕卡鲜草产量最低,为433 53.17 kg/hm2.高粱品种干草产量从高到低依次为3701＞Ms1990＞As6021＞F10＞健宝＞As6017＞绿巨人＞6022＞海牛＞As6013 ＞YCS＞超卡＞BT＞绝佳＞龙甜1号＞牛魔王＞6015 ＞6023＞帕卡.