토마토의 착과와 수확량은 여름철 비닐하우스내 고온스트레스로 인하여 감소하게 된다. 본 연구는 여름철 화천지역에 위치한 비닐하우스에서 지베렐린(GA3)과 2,4-Dichlorophenoxy Acetic Acid(2,4-D) 처리가 토마토의 수확량, 착과율, 착과 후 과실품질에 미치는 영향을 알아보기 위해 ‘Adoration‘ 품종을 이용하여 실험하였다. GA3 0-, 5-, 10-, 15mg·L−1와 2,4-D 0-, 5-, 10mg·L−1를 개화 초기에 처리한 후 착과율, 수확량, 과실품질과 관련된 형질을 관찰한 결과, GA3 10mg·L−1처리구에서 대조구에 비해 14.2%의 착과율 증가를 보였다. GA3처리구에서는 수확량, 과중, 상품과실 수에 유의한 차이가 있었다. 2,4-D를 개화기에 처리했을 경우 착과율, 수확량, 상품과의 과중에 영향을 미쳤으며 GA3과 2,4-D를 각각 5mg·L−1 농도로 혼합처리 하였을 때 가장 높은(62.5%) 착과율을 나타내었다. 과실크기와 고형물함량은 GA3처리구에서만 유의성 있는 차이를 보였다. 따라서 여름철 비닐하우스의 고온조건에서 GA3 0mg·L−1처리구와 2,4-D 5mg·L−1를 처리했을 때 착과율이 가장 높아 많은 수확량을 기대할 수 있을 것으로 판단된다.

본 연구는 베트남 하노이 지역에서 8가지 한국 토마토 품종 (핑크탑, 큐피랑, 슈퍼도태랑, 선레드, 선글러브, TP-7 플러스, 러블리 250, 광복)과 1가지 베트남 품종(FM 120)을 대상으로 봄-여름 및 가을-겨울 작기에 따른 수확량 및 과실 특성을 비교 분석하였으며, 그 결과는 다음과 같다. 1. 작기에 따라 초장, 경장, 주당 과실수 및 수확량(kg)은 유의성이 있었으며 가을-겨울 작기에서 높게 나타났다. 전체적으로 한국품종이 베트남 품종에 비해 높은 생육특성을 보인 반면, 과실수와 수확량에서는 베트남 품종이 우수하였다. 2. 토마토 과실의 주요 특성인 과장, 과폭 및 과중은 작기에 따라 유의한 차이를 보였으며 가을-겨울 작기에서 높은 수치를 나타내었지만 TSS 함량은 봄-여름 작기에서 높았다. 건물중과 비타민C 함량은 작기에 따라 유의한 차이가 없었다. 품종별 과실 특성은 한국 품종이 우수하였지만 비타민C 함량은 베트남 품종이 높았다. 3. 봄-여름 작기에서 한국품종의 경우 수확량 및 과실특성에서 가을-겨울 작기 재배에 비해 큰 감소를 보인 반면 베트남 품종은 큰 차이를 보이지 않았다. 따라서 본 실험에 이용된 8가지 한국 품종의 경우 봄-여름 작기보다는 가을-겨울 작기 재배가 적합할 것으로 판단된다.

Fifty-five sweet pepper (Capsicum annuum L.) germplasm from the Rural Development Administration (RDA) were analyzed for their fruit yield and fruit quality characters, including fruit weight, fruit size, pericarp thickness, total soluble content, fruit lobe, fruit shape, fruit surface and fruit color. Fruit yield per plot ranged from 200 g to 8150 g (average, 1884 g). Fruit fresh-weight per fruit ranged from 27.3 g to 200.0 g with an average of 97.2 g. Fruit length varied from 4.0 cm to 16.2 cm (average, 9.6 cm). Fruit length-to-width ratio ranged from 0.6 to 3.0 with an average 1.7. The fruit pericarp thickness ranged from 1.8 mm to 10.7 mm (average, 4.8 mm). Total soluble content was the highest (8.5˚ Brix) in K156286 and the lowest (5.3˚ Brix) in K156208 with the average value 6.7˚ Brix. Fruit lobes numbers varied from 2 to 4. Blocky, triangular, elongated, rectangular and round fruit shape identified among the sweet pepper accessions. Fruit surface varied from smooth to wrinkle and fruit color also varied. The presence of variability in fruit yield and quality traits within the sweet pepper genotypes can be utilized to develop high yielding sweet pepper variety with better fruit quality characters.

A field experiment was conducted to examine the fruit quality characters in second generation (F2) hybrid cultivar and to compare the fruit characters with original F1 hybrid cultivar of minipaprika (yellow and orange type) at the Research Farm, Hwacheon in July, 2010. Fruit characters varied within F2 population of each minipaprika type. In minipaprika yellow, fruit weight varied from 12.2 g to 50.8 g (average 28.5 g) and fruit length/width varied from 1.4 to 2.8 (average, 2.0). Pericarp thickness ranged from 1.8 mm to 4.1 mm (average, 2.9 mm). Total soluble solid (TSS) varied from 6.2˚Brix to 13.5˚Brix with an average of 8.7˚Brix. Fruit volume varied from 10.3 cc to 46.7 cc with an average of 24.4 cc. In minipaprika orange type, fruit weight ranged from 19.7 g to 42.4 g (average, 29.0 g) and fruit length/width varied from 1.5 to 2.6 (average, 2.0). Pericarp thickness varied from 2.1 mm to 4.1 mm with an average of 3.0 mm. TSS varied from 5.0˚Brix to 12.2˚Brix (average, 7.9˚Brix) and average fruit volume was 24.6 cc ranging from 10.7 cc to 35.0 cc. The average fruit quality characters in F2 population in both yellow and orange minipaprika did not differ from their F1 hybrid parent and F2 seed can be an additional way to supply high yielding hybrid cultivars at lower cost to the minipaprika growers.

Anthers of sweet pepper F1 cultivar ‘Special’ were cultured on Dumas De Vaulx (C medium), supplemented with 0.1mgL-1 2, 4-D and 0.1 mg · L-1 kinetin with 3% sucrose, and 0.32% phytagel. The calluses obtained were further sub-cultured on Murashige and Skoog (MS) medium without growth regulators for regeneration. Regenerated plantlets were grown in plastic pots under plastic house and characterized their cytological and morphological characters in spring, 2008. Twenty percent plantlets were identified as haploid plants after chromosome and ploidy analysis. Haploid plants contained 12 chromosomes, high stomatal density with small stomatal length as compared to diploid plants. Stomatal length in haploids was 23.3% smaller than diploids. Haploid plants were characterized as small leaf and petiole size, poor vigor, thin stem and short plant height, short internodes and small flower buds, fruit size and fruit weight as compared to diploid plants and most of the haploid fruits were seedless. SP55, SP62, SP68, SP72 and SP77 are found high yielding double haploids with high total soluble content (8.6, 8.7, 9.2, 9.1 and 9.8 ºBrix, respectively) and desirable fruit shape, and recommended them to exploit as inbred lines for heterosis breeding.

Sweet pepper inbred lines (KNU1003, KNU1006, KNU1007, KNU1009, KNU1015, KNU1017 and KNU2006) developed at Kangwon National University (KNU) through conventional means, inbred lines (5AVS1, 5AVS2, 5AVS3, 5AVS5, 5AVS7 and 5AVS8) collected at Rural Development Administration (RDA) and inbred lines (SP12, SP27 and SP14) derived from anther culture were used as female parents and anther culture derived homozygous lines (SP9, SP10, SP14, SP24, SP25, SP27, SP30, SP32, SP34, SP38, SP43, SP45 and SP51) were used as male parents to produce F1 hybrids. A total of 37 F1 hybrids were evaluated for fruit yield and quality characters in summer season, 2007. Variation in fruit number, fruit weight, fruit yield per plant and fruit volume was observed among the F1 hybrids. Superiority on yield over standard/commercial varieties were differed among F1 hybrids. Hybrid 5AVS8 x SP45 exhibited highest heterosis over Special (16.5%) and Fiesta (24.7%). Fruit quality characters (fruit length, fruit width, pericarp thickness, total soluble solid, fruit shape and fruit color) were varied among the F1 hybrids. Fruit number, fruit weight and fruit volume per plant were correlated with fruit yield. Based on the standard heterosis expressed by the hybrids and quality characters evaluation, KNU1017 x SP27, 5AVS1 x SP43, 5AVS5 x SP27, 5AVS8 x SP45, SP12 x SP38 and SP27 x SP25 hybrids were found to be superior over commercial cultivars and are selected. Inbred lines of these hybrid combinations can be used to produce F1 hybrid seed for commercial production.