Hipps N A, Pagès L, Huguet J G, Serra V
Station d'Agronomie, Centre de recherches d'Avignon, Domaine Saint-Paul, 84143, Montfavet, France.
Tree Physiol. 1995 Feb;15(2):95-103. doi: 10.1093/treephys/15.2.95.
Three controlled water supply treatments were applied to 1-year-old peach trees grown in root observation boxes. The treatments were: I(0), growth medium maintained at 50% field capacity; I(1), water supplied when daily net tree stem diameter change was negative or zero for 1 day; I(3) as for I(1) except that water was applied after net daily stem diameter change was negative or zero for 3 consecutive days. Trees in treatment I(0) had the greatest mean daily first-order shoot growth rates, and trees in treatment I(3) had the lowest shoot growth rates. Because leaf production rate (apparent plastochron) of first-order shoots was unaffected by treatment, differences in shoot length were due to differences in internode extension and not to the number of internodes. Trees in treatment I(0) had a greater number of second-order shoot axes than trees in treatment I(1) or I(3). Furthermore, an increase in the rate of growth of the first-order shoot axis was associated with an increased tendency for branching (i.e., the development of sylleptic second-order shoots). Increased leaf length was also associated with more frequent watering. Trees in treatment I(0) had the greatest root lengths and dry weights, and this was attributed to a greater number of first-and second-order (lateral) root axes compared with trees in the I(1) and I(3) treatments. The extension rate and apical diameter of first-order roots were reduced by the I(3) treatment. The density of second-order roots along primary root axes was not affected by any of the treatments.
对种植在根系观察箱中的1年生桃树实施了三种控制供水处理。处理方式如下：I(0)，生长介质保持在田间持水量的50%；I(1)，当每日树干净直径变化为负或为零持续1天时供水；I(3)，与I(1)相同，但在每日树干净直径变化为负或为零持续3天后供水。I(0)处理的树平均每日一级新梢生长速率最高，I(3)处理的树新梢生长速率最低。由于一级新梢的叶片产生速率（表观叶龄期）不受处理影响，新梢长度的差异是由于节间伸长的差异，而非节间数量的差异。I(0)处理的树比I(1)或I(3)处理的树有更多的二级新梢轴。此外，一级新梢轴生长速率的增加与分枝趋势增加（即，侧生二级新梢的发育）相关。叶片长度增加也与更频繁浇水相关。I(0)处理的树根系长度和干重最大，这归因于与I(1)和I(3)处理的树相比，其一、二级（侧生）根轴数量更多。I(3)处理降低了一级根的伸长速率和顶端直径。沿主根轴的二级根密度不受任何处理的影响。
