Does root pruning increase yield and water-use efficiency of winter wheat?

摘要: Apotanda fieldexperimentwereconductedtoassesswhetherseedingdensityinwinterwheataffectsgrainyield and water-use efficiency when combined with root pruning. Both experiments compared four treatments, namely (i) low (normal)plantdensitywithnorootpruning;(ii)lowplantdensitywithrootpruning;(iii)highplantdensity(25%higherthan density) no pruning; (iv) high plant density Roots to a depth of 25cm were cut back keep their length 13cm limit lateral spread from the plant. In pot experiment, two water regimes employed stem elongation: plants maintained at 85% field capacity, (ii) 55% capacity by regular watering. Low rainfall inspring terminal stage growth served as natural stress in experiment. field, higher induced biomass all sample depths anthesis. Root pruningsignificantlydecreasedtherootbiomassintheuppersoillayer(0-40cm)andincreasedtherootbiomassinthedeep soil layer (80-120cm). When was limited, increasing seeding 25% reduced grain yield, but adequatewaterincreasingtheseedingdensityincreasedthegrainyield.Rootpruningincreasedthegrainyield,buttherewas nointeractionbetweenseedingdensityandrootpruningongrainyieldineitherthepotsor field.Rootpruningreducedwater use between elongation anthesis which led more available maturity, increased rate flag leaf photosynthesis anthesis, whereas reverse true density. Measurements chlorophyll fluorescence suggested that initially pruning plants, pruned rapidly recovered so during filling level reduced. Increasing number spikes (fertile tillers), decreased yield per spike had effect on thousand-kernel weight. contrast, both pots, Under our experimental conditions, restricting size winter wheat water-limited environments.