Effective Tillering Pattern and Grain Yield on Different Seeding Dates in Barley

보리 파종기에 따른 유효분벽의 양상과 수량

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by difference in seeding date. Yield and yield contribution rates of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from September 1982 to July 1984. When barley was sowed 15 days earlier than or at the locally recommended sowing date (i.e. October 5), it produced more mainstem leaves than the that sowed 15 days later than the local recommendation. The effective tillers (i.e. ear-bearing tillers) were observed in concurrently occurring leaves up to 10/0 (abbreviation of the 10th mainstem leaf) from early and optimum sowed crops, while 9/0 from late sowed crops. Tillering followed the production rule of Gatayama(l952) which has the linear leaf appearance pattern. Early sowing produced more effective tillers, but the highest production of effective ears (i.e. ears heavier than 0.505g) was noticed in sowing at the recommended date. The tillers in the axil of first leaf in mainstem (abbreviated as 1) produced more effective ears than other mainstem tillers (i.e. primary tillers such as C, 2, 3 and 4). The tillers from the axil of first leaf, whether they were primary or secondary, always performed better in the production of effective tillers, grains per ear, grain weight, and grain yield per ear than those from the axil of coleoptile or prophyll. Other tillers from subsequent leaves were also inferior in production with the order of their appearance, thus making first leaf tillers as the best performer(e.g. 1 against C, 2, 3, 4 of primary tillers, 11 and 21 against 1P, 12, 13, 2P, 22 of secondary tillers). Even though the first leaf tiller from the first mainstem leaf(i.e. 11) emerged at a same time with the fourth mainstem leaf tiller(i.e. 4), it was always a better producer of ears and grains. The above observations of hierarchy among tillers were persistent irrespective of cropping conditions and treatments. Sowing at the recommended date produced more effective tillers and grains per ear than early or late sowing. In early and late sowings, more grains per effective ear were observed by early sowing, whereas more grains per ear were produced by late sowing. The order of performance in production of effective tillers and ears per plant was as follows: optimum > early > late sowings. In optimum sowing the mainstems were the highest in grain weight per ear, while the first leaf tillers were the ones in early sowing probably due to winter damage on mainstem ears. Yield contribution by the tillers was greater with the following order irrespective of sowing dates: mainstem, 1, 2, 3, C, 11, 12 and Cl. The contribution of CP, 2P, 21 and 31 varied with sowings.

보리의 안전생산기술 체계개선을 위하여 파종기의 조만에 따른 분엽별 생태적인 변화, 유효경 비율, 분엽경별 수량 구성요소와 기여도에 관하여 검토한 바 다음과 같은 결과를 얻었다. 1. 간장은 파종기 간에 큰 차이가 없었으나 분엽차위별 차이는 있었고 주관엽수는 조파구 13.2, 적파구 12.5, 만파구 11. 1매로 조파나 적파구는 만파구보다 1.4~2.1매가 많았다. 2. 유효경발생율은 주간을 제외하고는 조파구 > 적파구 > 만파구의 순으로 파종기가 빠를수록 2, 3차분엽에서 높았다. 유효경 발생율이 100%인 엽자로는 1차분엽중 조파구 1, 2, 적파구와 만파구는 1이었으며 어느 분엽절위에서나 동일모경의 동차위분엽은 자엽소 및 전엽분벽보다 다음 절에서 발생한 분벽, 동지분벽중에는 11, 동신분벽중에는 주간엽위의 하위절분벽이 강대경으로 유효경율이 높았다. 3. 주당 유효경수는 조파구 > 적파구 > 만파구의 순위이나 유효수수는 조파보다 적파구가 많았다. 4. 1수위수는 분벽의 발생시기가 빠른 주간 기부의 저위, 저차위분벽에서 많았고 입수도 유효경발생율과 같이 자엽소나 전엽분벽보다 상위1절의 분벽, 동지분벽중 11, 동신분벽중 주간절위가 저위의 저차위분벽이 강세를 보였다. 5. 포괄적인 유효수의 간입중은 파종기가 빠를수록 무거웠으나 동신엽, 동신분벽간의 간입중 차이는 일양성이 없었다. 6. 1종 자실중도 자엽소 및 전엽분벽보다 다음 상위1절의 분벽경에서 무거웠고 동지분벽중에는 11이 최대이었으며 동신분벽중에는 주간절위에서 저위, 저차분벽이 고위, 고차분벽보다 우세하였다. 7. 분벽의 수량기여도 상위10위까지의 벽자에 있어 전체평균기여도는 1, 2, 0, 11, 3, C, 21, C1, 12, 1P의 순이었으나 파종기의 이동에 따라 다소의 순위의 차가 있었다. 분벽경의 자실중은 $\ulcorner$전생우세$\lrcorner$의 대원칙하에서 다소의 차이를 보였으나 자엽소 및 전엽분벽보다 다음 상위1절의 분벽 즉 $\ulcorner$후생우세$\lrcorner$의 현상을 보여 이른바 가령현상을 나타냈다.