果树学报
果樹學報
과수학보
JOURNAL OF FRUIT SCIENCE
2008年
4期
449-453
,共5页
果实%叶片%水分转移%储水库%氚水爪踪
果實%葉片%水分轉移%儲水庫%氚水爪蹤
과실%협편%수분전이%저수고%천수조종
Fruit%Leaf%Water tranport%Water reservoir%Tritium water%Tracing
20世纪初创立的所谓"果实乃日中储水库"的理论,在70-80年代受到了挑战.反对者认为原来理论创立者所采用的是切枝试材而非完整植株,属于试验方法上的错误.他们怀疑切枝试材会迫使形成一种非自然的水势梯度.导致蒸腾的叶片能够从果实获取水分.本文报道氚水示踪法在完整植株上的试验结果,证明果实的水分完全可以被叶片抽走.此外,"去果实"和"留果实"的对比试验证明果实的存在有利于降低叶片在昼间的缺水程度,即叶水势相对较高.作者指出果实在夜间对水分的竞争力往往超过叶片,所以结果多的果树植株反而容易受旱而死.因此,单纯把果实比喻为"储水库",作为科学用语似不恰当.
20世紀初創立的所謂"果實迺日中儲水庫"的理論,在70-80年代受到瞭挑戰.反對者認為原來理論創立者所採用的是切枝試材而非完整植株,屬于試驗方法上的錯誤.他們懷疑切枝試材會迫使形成一種非自然的水勢梯度.導緻蒸騰的葉片能夠從果實穫取水分.本文報道氚水示蹤法在完整植株上的試驗結果,證明果實的水分完全可以被葉片抽走.此外,"去果實"和"留果實"的對比試驗證明果實的存在有利于降低葉片在晝間的缺水程度,即葉水勢相對較高.作者指齣果實在夜間對水分的競爭力往往超過葉片,所以結果多的果樹植株反而容易受旱而死.因此,單純把果實比喻為"儲水庫",作為科學用語似不恰噹.
20세기초창립적소위"과실내일중저수고"적이론,재70-80년대수도료도전.반대자인위원래이론창립자소채용적시절지시재이비완정식주,속우시험방법상적착오.타문부의절지시재회박사형성일충비자연적수세제도.도치증등적협편능구종과실획취수분.본문보도천수시종법재완정식주상적시험결과,증명과실적수분완전가이피협편추주.차외,"거과실"화"류과실"적대비시험증명과실적존재유리우강저협편재주간적결수정도,즉협수세상대교고.작자지출과실재야간대수분적경쟁력왕왕초과협편,소이결과다적과수식주반이용역수한이사.인차,단순파과실비유위"저수고",작위과학용어사불흡당.
The so-called "fruit as a midday reservoir" theory was queried and challenged in the 1970's and 1980's by the reason that the experimental methods the previous researchers used instead of intact plants were excised shoots, which might induce the development of unnatural water potential gradients. The present authors conducted experiments with potted and field-grown citrus plants with both tritium tracing and water potential measurements to verify the assumption that transpiring leaves are capable of drawing water directly from fruit. Translocation of tritiated water was detected from fruit to leaf, and the presence of fruit on a shoot might moderate, whereas the absence of fruit might accentuate the leaf water deficits during the day-time. It is pointed out that fruit may not necessarily be inferior to the leaves, as fruit may compete successfully with leaves for water during the night-time when their water potentials become lower than that of the leaves. It is considered that the figurative use of the word "reservoir" as a scientific jargon does not appropriately denote the actual behaviours of a living fruit.