| Study on dynamic of LA and DM accumulation and its relationships with yield were carried out in Keshan Wheat Breeding Institute in 2000-2002. The yield components and growth phases among the four eco-types were also compared. Four different eco-type genotypes, NKH 9, NE 7742, KF 4 and KL 3, were used in the study.The significant difference of LA on main stem among the eco-types was found. The peaks of both flag leaf area and the others in types A and B were much higher than that of C and D, but the decrease speed of LA was quite the contrary. The results also indicated that the LA duration of flag on main stem showed B>A>D>C in order. As to the tillers, it was the fastest in A, C and D, and B the lowestThe DM accumulation of main stem was quite difference between the eco-types used in the study. The result showed that A and B > D and C, and the accumulation patterns were not the same. The significant differences of the DM accumulation pattern of non-economic part on main stem between the eco-types and in relation to the redistribution of DM after flowering were found. The order of flag DM weight was A>B>C>D, and B>A>C>D in DM weight of leaf sheath. And the DM played important role in grain DM accumulation. The DM weight of peduncle in types A and B was much higher than that of C and D. And B decreased more quickly than other three types because of moving more DM from peduncle into economic part. As to the DM weight of leaves on main stem, leaves excluding flag leaf on main stem, and total DM of the whole plant, A and D is much more higher than that of C and D. The pattern of DM accumulation in tillers could be fixed with the Logistic equation. All the cures had the same shape "S", but the peaks were different markedly between the eco-types, and ranked A>B>C>D. And no difference could be found between A and B statistically.The correlation between weight of leaf DM per unit leaf area, grain:LA (cm2) ratio, harvest index and yield indicated that LA and DM accumulation played more important role in yield formation in eco-types A and B. B ranked the first in grain:LA (cm2) ratio, then C, A and D in order, but B>D>C>A in harvest index.The difference of growth and development occurred in four eco-types was found in the length of the whole growth period and the structure of growth duration. Type A is late in maturity, and B, C, D are early-mid or early ones. The duration from emergence to nodding is longer in type A and B, but shorter from nodding to heading (or flowering) and normal from heading (or flowering to mature) in type B when comparing with type A. As to types C and D,all the three growth durations are shorter.On the basis mentioned above, the high yield in types A and B could be reached via the high DM accumulation of individuals with least tillers. On the contrary, high plant density and much more spikes come from tillers play important role in high-yielding production of types C and D.
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