Occurrence of Weedy Rice as Affected by Cultural Practices

The inheritance of resistance to bacterial blight in a Tongil-type rice cultivar 'Changseongbyeo' was studied using a Korean isolate HB9101. which belongs to race K1 . The resistance of Changseongbyeo to the HB9101 was controlled by a single dominant gene. This gene was allelic with Xa-1 gene and linked to Ig gene on chromosome 4 with the recombination value of 7.5%.

A cDNA Fragment encoding iron storage protrin generated by polymerase chain reaction(PCR) using highly conserved regions of ferritin related genes were used to sereen a red pepper cDNA library. cDNA clone was designated as Fp1. Fp1 clone contatines a 5' nontranslated region of 51dp containing stop conds. Down stream from 5' UTP. an open reading frame of 750bp was observed. followed by a 3' UTR of 272bp. The deduces amino acid sequence of red pepper protein(Fp1) showed 84%, 48% and 36% identity with soybean(SolC). human(HuL H) and horse spleen(HoS-L) ferritin mRNA accumulation in response to iron. Ferritin mRNA accumulation was transient and particularly abundant in leaves. reaching a maxmum at 12h. The level of ferritin mRNA in roots was affected to a lesser extent than in leaves.

Indica 벼의 원형질체들로 부터 효과적인 식물체 재분화 방법을 개발하였다. 이 방법은 배형성 진탕 세포 배양체로 부터 나출된 원형질체들을 feeder cell들이 agarose에 embedded된 배지 표면에 놓인 filter membrane 위에 배양하는 것이다. Feeder cell로서 Lolium multiflorum 세포배양체를 사용했을 때가 Oryza ridleyi를 사용했을 때보다 효과적이었고, 원형질체 평탄효율은 세포 배양체 age에 따라 달랐지만 최고로 0.68％ 까지 증가되었다. Carbohydrate source로서 maltose를 사용하거나 maltose와 sucrose를 1:1로 조합했을 때가 sucrose 단독으로 사용했을 때보다 식물체 재분화율이 증가되었고, 고농도의 agarose를 이용하여 원형질체로부터 유도된 캘러스를 dehydration시켰을 때 또한 재분화율이 괄목하게 증가되었다. 식물체 재분화율은 control 캘러스로부터 3.1∼30.6％ 였지만 dehydration처리한 캘러스로부터는 30.7∼70.7％까지 증가되었다. 원형질체로 부터 유도된 식물체들은 형태적으로 정상이며 개화했다.