最近的一些研究表明，干旱脅迫能影響葉子發(fā)育以及儲(chǔ)藏根的生長,，因此會(huì)對糖用甜菜的產(chǎn)量造成影響,。為了研究干旱條件下蔗糖的累積情況,，糖用甜菜研究所科學(xué)家C. M. Hoffman對甜菜儲(chǔ)藏根的生長,、離子和溶質(zhì)積累的變化情況進(jìn)行了考查。他進(jìn)行了兩組盆栽實(shí)驗(yàn),，其中一組使糖用甜菜保持中度干旱條件,，另一組則使糖用甜菜和飼料甜菜處于極度干旱狀態(tài)。
結(jié)果表明干旱脅迫使甜菜的根和葉子產(chǎn)量下降,，儲(chǔ)藏根中蔗糖的濃度也有所降低,，而鉀、鈉,、氨基酸和葡萄糖等溶解物的濃度則有所升高,。蔗糖和溶解物間的這種負(fù)相關(guān)關(guān)系表明溶解物濃度的增加限制了蔗糖積累。（生物谷Bioon.com）
生物谷推薦英文摘要：
Journal of Agronomy and Crop Science DOI: 10.1111/j.1439-037X.2009.00415.x
Sucrose Accumulation in Sugar Beet Under Drought Stress
C. M. Hoffmann
Drought stress may affect sucrose accumulation of sugar beet by restricting leaf development and storage root growth. The objective of this study was to identify changes occurring in the storage root of Beta beets in growth characteristics and ions and compatible solutes accumulation under drought with regard to sucrose accumulation. Two pot experiments were conducted: (1) sugar beet well supplied with water (100 % water capacity), under continuous moderate (50 %) and severe drought stress (30 %), (2) sugar beet and fodder beet well supplied with water (100 %) and under continuous severe drought stress (30 %). Under drought stress, the ratio of storage root to leaf dry matter of sugar beet decreased indicating a different partitioning of the assimilates. The sucrose concentration of the storage root was reduced. In the root, the number of cambium rings was only slightly affected, although drought stress was implemented already 6 weeks after sowing. In contrast, the distance between adjacent rings and the cell size was considerably restricted, which points to a reduced expansion of existing sink tissues. The daily rate of sucrose accumulation in the root showed a maximum between 16 and 20 weeks after sowing in well-watered plants, but it was considerably reduced under drought stress. The concentration of compatible solutes (K, Na, amino acids, glycine betaine, glucose and fructose) decreased during growth, while it was enhanced because of drought. However, when sucrose concentration was added, a constant sum of all examined solutes was found throughout the vegetation period. It was similar in sugar beet and in fodder beet despite different concentrations of single solutes, and the total sum was not affected by water supply. A close negative relationship between the concentration of compatible solutes and sucrose occurred. It is therefore concluded that the accumulation of compatible solutes in the storage root of Beta beets under drought might be a physiological constraint limiting sucrose accumulation.
