[目的]研究不同行距配置对木薯产量、品质及薯构型的影响,优化木薯机械化种植与收获模式的农艺农机参数.[方法]以我国主栽的机械化木薯品种华南205(SC205)为材料,采用田间试验,平地模拟机械化种植模式,设等行距(0.8+0.8)m(CK)及宽窄行(1.0+0.5)m(T1)、(1.0+0.6)m(T2)、(1.0+0.7)m(T3)、(1.2+0.4)m(T4)、(1.2+0.5)m(T5)、(1.2+0.6)m(T6)共7种行距配置,于收获期测定薯块产量、薯块可溶性糖和淀粉含量、薯块性状及薯构型.[结果]1)两年中,T6木薯鲜薯产量、薯干产量均最高,较T1显著增产19.19％～24.89％和19.61％～30.56％.2)T6木薯块根的可溶性糖和淀粉积累量均处于较高水平,较T1分别明显提高21.38％～31.38％和27.67％～31.51％.3)两年中,T1垂直行向半幅宽均最窄,为19.72～20.50 cm,且薯长均最短,为13.01～14.57 cm.4)当收获单株的垂直行向半幅宽为30.0 cm、深度为25.0 cm时,所有处理均可收获98.50％以上的鲜薯产量,其中T6收获的鲜薯产量最高,达41.79 t/hm2,收获比例为99.42％.[结论]在木薯品种SC205平地机械化种植模式中,推荐(1.2+0.6)m的宽窄行配置,收获机在窄行间的双行作业幅宽为120.0 cm、深度为25.0 cm.

In order to optimize the cultivation space of cassava maize intercropping system,a total of five different modes,including equidistant row sole cassava（MS 1 ）,wide-narrow row sole cassava（MS 2 ）,equidistant row cassava intercropping 1 row maize（MI 1 ）,wide-narrow row cassava intercropping 1 row maize（MI 2 ）,wide-narrow row cassava intercropping 2 rows maize（MI 3 ）were set up.Then the aboveground agronomic traits and the yield of cassava and maize were measured,the storage root configuration（SRC）,flesh quality of cassava root,and the soil physicochemical properties were investigated.The results showed that:Compared with MI 1 and MI 2 ,MI 3 increased maize plant height by 9.5%to 11.5%,stem diameter by 14.4% to 18.1%,the maize total ear number by 45.1% to 59.7% and the fresh ear yield by 70.9%to 76.4%.Compared with cassava monoculture,a“competition-recoverytranscendence”phenomenon was existed in cassava-maize-intercropping（C-M-I）system,and C-M-I also increased the cassava yield of fresh storage root（FSR）by 31.4% to 56.2%,dry storage root by 34.7% to 58.4%,starch by 37.5% to 60.1%,as well as significantly increased the harvest index（HI）by 35.1% to 40.5%.The increase of the MI3treatment was the largest.The half width along the ridge direction and across the ridge direction or depth of SRC were 30.2-36.2cm,20.6-26.4cm,22.5-24.7cm,respectively.Furthermore,about 95.1%-98.5% of the number of storage root（NSR）and 98.1%-99.8% of the weight of storage root（WSR）were distributed within 0-40cm along the ridge direction,≥86.9% NSR and ≥97.2% WSR were distributed within 0-30cm across the ridge direction,and 93.7%-99.2% NSR and 97.6%-99.9% WSR were distributed under 0-25cm soil.SRC of MI 3 displayed the widest and deepest distribution.There was no significant difference among all treatments with the flesh quality and taste of cassava root.The soil physicochemical properties after cassava harvest showed that C-M-I was better than cassava monoculture,wide-narrow row was better than equal spacing and among them MI 3 was the best.Overall,MI 3 has the greatest advantages in the above-ground growth,SRC,yield and soil physicochemical properties,so it is recommended to be popularized and applied in cassava production of Hainan.

平地宽窄行(1.0 m+0.6 m)模拟机械化种植模式下,以我国主栽机械化木薯品种'NZ199'为对象,设置平放顺向对称(T1)、平放顺向交错(T2)、平放斜向对称(T3)、平放斜向交错(T4)、斜插反向对称(T5)、斜插反向交错(T6),共6种双行种茎排布方式,研究其对鲜薯产量、薯块特征及薯构型的影响,以期筛选适宜的木薯机械化种植模式与收获农艺农机参数.结果 表明,斜插较平放有助于提高鲜薯产量;斜插反向交错、平放顺向对称的鲜薯产量均较高,分别达41.92～50.11、38.55～48.42 t/hm2,二者结薯的平均垂直行向半幅宽均较窄,仅为22.92～24.09 cm;当收获单株的垂直行向半幅宽为30.0 cm、层深为25.0 cm时,斜插反向交错与平放顺向对称的收获鲜薯产量占比、鲜薯产量均较高,分别达97.54％～98.87％、38.12～40.87 t/hm2.综上,在平地宽窄行机械化种植模式中,推荐斜插反向交错和平放顺向对称种植方式,建议收获机在窄行间的双行作业幅宽120.0 cm、犁深25.0 cm,则可收获98％的鲜薯产量.

以2个木薯品种'SC205' 和'SC124' 为研究对象,设置不施钾(K0,K2O 0 kg/hm2)、低钾(K50,K2O 50 kg/hm2)、中钾(K100,K2O 100kg/hm2)和高钾(K200,K2O 200kg/hm2)4个施钾量处理,测定收获期木薯的农艺性状、鲜薯产量及其构成指标、可溶性糖组分含量、淀粉组分含量等指标.结果表明:(1)与不施钾相比,施钾量达100 kg/hm2以上时,能显著提高木薯株高、茎径、单条薯重;施钾量达50 kg/hm2以上时,能显著提高鲜薯产量,其中'SC205' 和'SC124' 的鲜薯产量增幅分别达59.2％～131.7％和51.4％～127.9％,在施钾量(K2O)为100 kg/hm2时鲜薯产量达到最大值;(2)施钾量对不同组织可溶性糖组分含量及总淀粉含量、支链淀粉含量均有显著影响;品种与施钾量间交互作用对蔗糖含量具有显著影响,对其他可溶性糖组分及淀粉各组分均无显著影响(P＞0.05);(3)相关性分析表明,各组织的可溶性糖组分含量与块根淀粉组分含量间具有负的相关性,其中块根的可溶性糖组分与块根总淀粉含量具有显著或极显著的负相关,茎秆的葡萄糖和蔗糖含量与块根总淀粉含量具有显著负相关.综上所述,合理施钾促进了可溶性糖向淀粉的转化,进而有利于木薯鲜薯产量和品质的形成,对连作条件下木薯的提质增效具有重要的实践意义.

[目的]探究不同间作模式对木薯和玉米共生期间的农艺性状、根系分布、土壤理化性状和根系养分含量的影响,为优化木薯间作玉米高产高效栽培技术提供理论依据.[方法]以华南9号食用木薯和特早熟糯玉808鲜食玉米为试验材料,设等行距、宽窄行单作木薯及木薯等行距间作1行玉米、宽窄行间作2行玉米共4个处理,对比分析二者共生期间的农艺性状、三维立体根系分布以及不同土层的土壤理化性状和根系养分含量.[结果]宽窄行的木薯和玉米地上部长势均优于等行距.宽窄行间作比等行距增产玉米21.1％.单株的玉米、木薯根系均以植株为中心水平对称,由里向外呈由密至疏分布;单株玉米根系呈上密下疏、上窄下宽分布,68.7％～77.3％根重、46.2％～49.4％根长、52.7％～59.3％根表面积聚集在玉米行两侧各宽10 cm、深10 cm土带内;单株木薯根系呈上密下疏、上宽下窄分布,细根的50.8％～61.4％根长、47.7％～57.2％根表面积聚集在木薯种茎基端线两侧各宽20 cm、深10 cm土带内,而粗根的35.7％～42.0％根长、39.3％～48.8％根表面积和35.9％～46.3％总根重聚集在木薯种茎基端线两侧各宽20 cm、种茎中线两侧各宽30 cm、深10 cm土块内.土壤碱解氮、速效磷钾及作物根系磷钾含量基本呈表层(0～10 cm)>中层(10～20 cm)>深层(20～30 cm)的分布规律,而作物根系氮含量则表现相反规律;土壤和木薯、玉米根系的氮磷钾含量基本呈间作>单作,其中,宽窄行间作玉米的绝大部分养分指标为最高.[结论]玉米和木薯根系虽穿插生长,但其密集生长带(块)互不重叠,为弱竞争关系,以宽窄行为优,且宽窄行木薯间作玉米有利于提高两者的根系养分、土壤养分含量和玉米产量,故生产中推荐宽窄行木薯间作玉米模式.

阐述了我国食用木薯及其休闲利用现状,并针对目前我国木薯淀粉、酒精加工业和种植业面临的行情低迷、经济效益差的困境,提出了加强科技支撑,争取政策扶持;探索传媒和电商新模式,拓展市场销路;探索休闲新模式,提高木薯附加值;弘扬传统文化,开发文创产品的对策建议.

为筛选有助于木薯抗逆栽培的植物生长调节剂,开展了植物生长调节剂浸种对袋栽木薯苗生长的影响研究.结果表明,与不浸种比较,矮壮素、缩节胺和清水浸种可提高木薯苗的出苗率、株高、茎径,提高其细根的总根长、总表面积和总体积,提高根茎叶的干重、根冠比、净光合速率、薯干淀粉含量,部分处理和指标之间差异达显著水平,以矮壮素效果为优;吲哚丁酸浸种对木薯苗部分生长指标有促进作用,部分指标差异达显著水平,但多效唑、烯效唑、乙烯利浸种对木薯苗部分生长指标有抑制作用,部分处理和指标间差异达显著水平,而2,4-D浸种不能出苗.

以华南12号木薯种茎为试验材料,分别采用不浸种(ck),清水(ck0),5,20,40,60g·L-1石灰水浸泡木薯基部、中部和顶部茎段14 h,研究各处理对木薯苗生长的影响.结果 表明:基部和中部茎段的出苗率及成活率均显著高于顶部茎段;浸种处理的出苗率均高于不浸种处理,以清水和20％石灰水浸种为优.结论:基部和中部茎段优于顶部茎段,推荐清水和20 g·L-1石灰水进行浸种技术.

不同品种木薯的薯块(块根)在土壤中的空间分布特性即薯构型,直接影响机械收获的效果.为探索木薯薯块在土壤中的空间分布特性,本研究通过抽样调查,研究了典型木薯品种华南205、南植199和新选048的薯构型,探讨适宜机械化收获的木薯品种,确定木薯机械化收获的技术参数.结果表明,华南205和南植199的薯块空间分布较为适宜机械化收获,单株木薯的最优收获半幅宽为0.0～35.0 cm、收获层深为0.0～25.0 cm,在此条件下,华南205的薯数占比和薯重占比均达到100.0％,南植199达96.0％以上.综合分析,确定木薯收获机的单株木薯半幅收获宽度为35.0 cm、收获深度为25.0 cm,该研究结果可为木薯收获机械的研究设计提供参考依据.

The cassava variety "Nanzhi 199" was used as experimental material, five treatments for seed stems were de?signed as follows: not soaking seeds ( CK1) , soaking seeds in water for 12 h ( CK2) , soaking seeds in 2％ lime solution for 12 h ( Ca1) , dipping seeds in lime slurry ( Ca2) and dipping seeds in lime powder ( Ca3) , and the effects of these treatments on the seed stem germination and seedling growth of cassava cultivated in nutritional bags were studied. The results showed that:in com?parison with CK1, the treatments CK2 and Ca1 could enhance the emergence rate, plant height, stem diameter, root total length, root total surface area, root biomass, stem biomass, leaf biomass, root-shoot ratio, and contents of soluble sugar, starch and cal?cium in tuber roots of cassava seedlings; while the treatments Ca2 and Ca3 inhibited the growth of cassava seedlings. Therefore, soaking seeds in water or 2％ lime solution for 12 h could promote the seed stem germination and seedling growth of cassava, and soaking seeds in 2％ lime solution had the best effects.