CAJ | 학술논문

基于覆膜和无膜处理对夏薯土壤相对含水量动态变化影响的研究，通过营养液水培和PEG-6000模拟干旱等方式研究6个甘薯品种在正常供水（模拟覆膜）和梯度干旱（模拟无膜）处理条件下的根系生物学性状。结果表明：覆膜使土壤相对含水量的降低缓慢而避开干旱胁迫的影响，而无膜处理的土壤相对含水量降低迅速。在浇足窝水的情况下，即使20天内无水分补充，覆膜土壤的相对含水量仍能保持在60％以上；而在无膜条件下，栽后6天为夏薯发生干旱胁迫的临界时间，且从轻度干旱胁迫到重度干旱胁迫的过程短，仅2天。不仅如此，与覆膜处理相比，干旱情况下无膜处理的甘薯根长、根投影面积、根表面积、根平均直径、根体积、根鲜重和根干重等指标均显著降低。而品种间比较发现，覆膜情况下色素提取型甘薯根系生长快、根量多，遭遇干旱胁迫后，色素提取型甘薯根系生物学性状降低幅度最大，对水分变化表现更敏感。6个甘薯品种根长、根表面积和根体积主要集中在平均直径大于0．45 mm的不定根上。总之，地膜覆盖有利于减缓土壤水分损耗，促进夏薯早发根、多发根，降低干旱胁迫对根系建成的不利影响。
기우복막화무막처리대하서토양상대함수량동태변화영향적연구，통과영양액수배화PEG-6000모의간한등방식연구6개감서품충재정상공수（모의복막）화제도간한（모의무막）처리조건하적근계생물학성상。결과표명：복막사토양상대함수량적강저완만이피개간한협박적영향，이무막처리적토양상대함수량강저신속。재요족와수적정황하，즉사20천내무수분보충，복막토양적상대함수량잉능보지재60％이상；이재무막조건하，재후6천위하서발생간한협박적림계시간，차종경도간한협박도중도간한협박적과정단，부2천。불부여차，여복막처리상비，간한정황하무막처리적감서근장、근투영면적、근표면적、근평균직경、근체적、근선중화근간중등지표균현저강저。이품충간비교발현，복막정황하색소제취형감서근계생장쾌、근량다，조우간한협박후，색소제취형감서근계생물학성상강저폭도최대，대수분변화표현경민감。6개감서품충근장、근표면적화근체적주요집중재평균직경대우0．45 mm적불정근상。총지，지막복개유리우감완토양수분손모，촉진하서조발근、다발근，강저간한협박대근계건성적불리영향。
Based on the influences of film mulching and non -film mulching on dynamic change of rela-tive water content in soil ( RWCS ) , the root biological characters of 6 sweet potato varieties were researched under normal water supply ( stimulating film mulching ) and gradient drought ( stimulating non -film mulc-hing) by hydroponics and treated with PEG -6000.The results showed that RWCS decreased slowly under film mulching treatment , which made sweet potato escaped from drought stress , while that under non -film mulching treatment decreased rapidly .In the case of adequate water supply when transplanting , RWCS would maintain over 60%even though without water supply for 20 days.Under non -film mulching treatment , the sixth day after transplanting was the critical time of drought stress , and the process from mild drought stress to severe drought stress took only 2 days.Compared with film mulching treatment , the root length, projected are-a, superficial area, average diameter, volume, fresh weight and dry weight of the 6 sweet potato varieties sig-nificantly decreased under non -film mulching treatment .Intervarietal comparison showed that the root of pig-ment extraction type sweet potato grew faster and more under film mulching treatment , and its biological char-acters decreased faster when encountered drought stress ,so it was more sensitive to moisture change .The root length, superficial area and volume of the 6 sweet potato varieties mainly located on adventitious roots whose diameter was over 0.45 mm.Above all, film mulching could retard water loss of soil , promote summer sweet potato rooting earlier and more , and decrease negative effects of drought stress on root formation .