Studied On Super High Yield Formation And Its Eco-physiological Characteristics Of Ordered Transplanting And Optimized Broadcasting Rice

In order to research super high yield formation and ecophysiological characteristics of ordered transplanting and optimized broadcasting rice, a experiment with super japonica rice wuyunjing24and nanjing44as material was carried out in hai’an county and agricultural college of yangzhou university during2010-2011comparing three planting methods including ordered transplanting (OT), optimized broadcasting (OB) and cast transplanting (CT) using dry-raising seedlings in plastic plates with mechanical transplanting (MT) to investigate super high yield formation, the photo synthetic and matter production characteristics, tillering characteristics, root system morphological and physiological characteristics, nitrogen uptake and utilization, plant type, population lodging resistance and rice quality. Then New rice super high yield cultivation type was explored and it could provide theoretical and practical basis for stable super high yield light and simple cultivation for broadcasting rice. The main results were as follows:1. Rice yields under OT and OB were significantly different CT from CT and MT with the trend of OT>OB>CT, and under different holes-gathered were2-hole>3-hole>1-hole. Compared MT and CT, yield of OT and OB with2-hole and3-hole were more than11t hm-2, while CT and MT were about10-10.5t hm-2. Using methods of ordered transplanting and optimized broadcasting rice seedlings had the better population quality with earlier seedling establishment at the beginning, and their LAI, leaf area duration, grain-leaf ratio, matter production, accumulation in each growing stage, and net photosynthetic rate and matter translocation in later growing stages were all significantly or very significantly superior to those of cast transplanting. Moreover, in late growing stages, they showed comparatively better population light transmittance and ventilation, slower senescence, and higher matter production and lodging resistance as well. The transplanting hill number for of3-and2-hole closely gathered plates were30-60percent less than that for single-hole ones, which improved transplanting speed. And2-hole seedlings kept higher matter production and lodging resistance in middle and late growing stages of which the yield was higher than3-hole seedlings and1-hole seedlings. With their higher population starting point, earlier seedling establishment, proper matter accumulation in early growing stage as well as higher matter production, accumulation and translocation ability in later growing stages, ordered transplanting and optimized broadcasting methods were capable of leading to the stable super high yielding cultivation of super rice. Two-hole plate transplanting seedlings showed better matter production and obvious growth superiority during the whole growth stage, and3-hole one also showed growth superiority in some aspects, which could lead us to the conclusion that2-and3-hole plate seedlings ordered transplanting are new-typed cultivation patterns of super high yielding in super rice.2.(1)Tillers emerging and earbearing:To OT and optimized OB rice, the primary tillers emerged from leaf1to leaf6on main stem and the secondary tillers in1/1,1/2,1/3, among them leaves3to5were the superior positions for tiller emerging and panicle formation and primary tillers accounted for65-70%. While the primary tiller of CT rice plant emerged from leaf1to leaf6and secondary tillers in1/1,1/2,1/3,2/1,2/3, among them tillers emerged2leaf positions more than OT and OB and leaves3to5were the superior positions for tiller emerging and panicle formation. And primary tillers of CT accounted for62-64%and secondary tillers accounted for70-78%were more than OT and OB. The primary tillers of MT rice plant emerged from3-7among them leaf4to leaf6were superior positions for tiller emerging and panicle formation. The primary tillers ratio of nanjing44under MT were among OB treatments and wuyunjing24were higher than OT, OB and CT, while secondary tillers ratio showed the opposite trend. And the primary tillers ratio were OT<OB<CT among different transplanting treatments while secondary showed the opposite trend.②Tillers emerging leaf positions among different holes treatments were the same as panicle formation, and the primary tillers emerging number, panicle formation rate and panicle number were2-hole>3-hole>1-hole, while the secondary2-hole,1-hole>3-hole.(2) Tillers’contribution to yield and panicle traits:①The primary tillers’accounted for90%of yield of OT and OB rice while CT85%. And spike lets number per panicle,1000-grain weight, seed-set rate, one panicle weight, grain density and yield among transplant ways were OT>OB>CT, MT.②Among different holes treatments there were no significant variations of the primary tillers’contributions to yield while the secondary tillers’ contributions to yield were2-hole,1-hole>3hole. And spikelets number per panicle, one panicle weight were3-hole,2-hole>1-hole while grain density, grain yield per plant, and population grain yield were2-hoel>3-hole,1-hole. Tillers emerging rate, panicle formation rate, spikelets number per panicle,1000-grain weight, seed-set rate, one panicle weight and grain density of the primary tillers were all higher than the secondary tillers, and stem accounted for more than20%of yield, so the primary and low tillers’superiority of OT and OB rice were larger.3. Root length, number and weight of3-hole seedlings had obvious advantages at7d after transplanting and2-hole seedlings had more obvious advantages at15d after transplanting. Root dry weight, root shoot ratio and root activity of root system at each stage were OT>OB>CT>MT, while treatments of different holes had a trend of2-hole>3-hole>1-hole. And root total absorbing surface area, active absorbing area, ratio of active absorbing surface area to total absorbing surface area and root bleeding sap showed the same trend too. Root dry weight, root shoot ratio, root activity, total absorbing surface area, active absorbing area, ratio of active absorbing surface area to total absorbing surface area and root bleeding sap had very significant positive correlation with grain yield. Root at the depth of top0-5cm accounted for more than70%while at depth of top0-10cm accounted for more than90%. And root dry weight, root volume and root weight density at each layer showed the trend of OT>OB>CT,2-hole>3-hole>1-hole, Root weight ratio at the depth of5-10cm,10-15cm and15-20cm showed the same tend. And root dry weight at each layer was very significantly correlated to grain yield, and root at the upper layer made great contributions to the grain yield, and the contribution rate to yield of root at the top depth of0-10cm was more than90%. Ordered transplanting and optimized broadcasting rice had better root growth, higher root activities and more reasonable root distribution at later growing stage which were the characteristics of underground and physiological basis for super high yield. 4.(1) Ordered transplanting and optimized broadcasting rice had lower N content at the whole stage and lower N accumulation at CS(critical stage for effective tillering) and ES(elongation stage), and N accumulation after elongation stage(ES) were very significantly or significantly higher CT, N accumulation and ratio were OT>OB>CT. And2-hole and3-hole plants kept higher N content and ratio than1-hole at each stage with proper N accumulation before ES and stronger N uptake ability after ES, and N accumulation, ratio and N uptake rate at each stage were2-hole>3-hole>1-hole.(2) N recovery efficiency, agronomic efficiency, physiological efficiency, partial factor productivity, N requirement for100kg, nitrogen use efficiency for biomass production, nitrogen use efficiency for grain production, nitrogen harvest index and grain among different transplanting ways showed the trend of OT>OB>CT, MT. N use efficiency, partial factor productivity and NHI among different holes treatments were2-hoel>3-hole>lhole, while N requirement for100kg, nitrogen use efficiency for biomass production, nitrogen use efficiency for grain production showed the opposite trend.(3) Root, clum sheath, leaf and panicle and total plant dry weight among different transplanting ways were OT>OB>CT, and2-hoel>3-hole>lhole among different holes treatments. N content and accumulation in root and panicle after heading showed the trend of OT>OB>CT, while the opposite trend in clum and sheath and leaf. And N content in leaf and panicle among different holes treatments were2-hoel>3-hole>lhole while there were no significant differences between N content in clum and sheath at heading and in root at mature. And N accumulation among different holes treatments in each organ were all2-hoel>3-hole>1hole. Ordered transplanting and optimized broadcasting rice had larger N transportation and higher transportation rate from stem, sheath and leaf to panicle and stronger root N uptake ability and N transportation and transportation rate among different holes treatments were2-hoel>3-hole>lhole. Ordered transplanting and optimized broadcasting rice had rational N content and accumulation at early stage and stronger N uptake ability at each stage and higher N accumulation, transportation and transportation rate which is the nutritional mechanism of OT and OB rice super high yield formation.5.(1) The lodging resistance was significantly different between different transplanting types. Lodging resistance of ordered transplanting was strongest with the lowest lodging index (LI) and population lodging index (PLI), however, the weakest to cast-transplant. And the lodging resistance of2-hole closely gathered rice was higher than3hole closely gathered and single hole rice.(2)The breaking fore (BF) of the basal four internodes was very significantly and positively correlated to LI and PLI which was the important factor affecting the lodge resistance. Moreover, the breaking force of the1st,2nd,3rd,4th internode had significant or very significant positive correlation with plant height, gravity center height, culm diameter, culm wall thickness, dry weight of culm, dry weight of leaf and sheath, dry weight of unit internode, length and fresh weight from basal internode to top, bending moment while significant or very significant negative correlation with the ratio of gravity center height to plant height and internodes length.(3) The strong lodging resistance of ordered transplanting and optimized broadcasting rice relied on the short and thick basal internode length, thick culm wall and good fulfilling for stem, especially for2-hole gathered and3-hole gathered rice.2-hole gathered and3-hole gathered ordered transplanting plants have strong lodging resistance which is a new type simplified cultivation for high yield and super high yield.6. The top3leaves of OT and OB rice were longer than CT and leaf base angle (LBA), angle between stem and leaf (ABSL) and droop angle(DA) were relatively lower. And3top leaves length among different holes treatments showed the trend of2-hole>3hole>1-hole while LBA, ABSL and DA2-hole the opposite trend. Leaf length was very significantly positive correlated to No. of grains per panicle, one panicle weight and grain yield while very significantly negative correlated to No. of panicles, while LBA, ABSL and DA showed the opposite trend. OT and OB rice kept higher LAI, effective LAI, SPAD in flag leaf and low decay after heading rate and LAI, effective LAI, SPAD in flag leaf among different treatments were2-hoel>3-hole>1-hole. Leaf site height and relative leaf site height among different transplanting ways were OT>OB>CT and among different holes treatments2-hole,3-hole>1-hole. And Leaf site height and relative leaf site height of top3leaves and distance of leaf occiput between1st and2nd leaf from top were very significantly or significantly and positively correlated to yield, grain weight, No. of grains per panicle, seed setting rate and1000-grain weight while very significantly and negatively correlated to effective panicles. Panicle length, grain density and stem and sheath weight were very significantly or significantly and positively correlated to No. of panicle, one panicle weight and yield while very significantly and negatively correlated to effective panicles. And plant height was significantly and positively correlated to No. of panicle and yield while stem length not significantly to yield and its components.7.(1) Processing quality. The brown rice rate (BR), milled rice rate (MR), head milled rice rate (HMR) among different transplanting ways were all ordered transplanting (OT)>optimized broadcasting (OB)>cast transplanting (CT), mechanical transplanting (MT) and among different holes treatments were all2-hole>3-hole>1-hole, so it is concluded that ordered and sparse transplanting was beneficial for improving rice processing quality.(2) Appearance quality. Chalkiness rate (CR), chalkiness size (CS), chalkiness degree (CD) among different transplanting ways showed the trend of OT>OB>CT. CR, CS and CD among different hole treatments were2-hole>3-hole>1-hole, and that the more tillers’intense growth competition in2-hole and3-hole weakened the appearance quality.(3) Cooking and eating and nutritional quality. Gel consistency (GC), peak viscosity, trough viscosity and breakdown among different transplanting ways were OT>OB>CT, MT. And there were no significant changes in amylose content and protein content among different holes treatments while peak viscosity and breakdown showed the trend of2-hole>3-hole,1-hole and the final viscosity and setback2-hole,3hole>1-hole. Ordered transplanting and optimized broadcasting improve rice processing, appearance and cooking and eating and nutritional quality in more traits, especial2-hole and3-hole transplanting improve the rice quality apparently(except processing quality).