본 실험은 초화류인 코레우스의 삽목시 삽수의 발근율을 높이기 위하여 배양액과 NAA 및 IBA처리 효과를 조사하였다. 모래삽목보다는 배양액을 이용한 것이 발근소요일이나 생육면에서 월등히 효과적이었다. 특히 배양액 농도는 일본 원시표준액보다는 표준액의 1/4 배양액 농도에서 재배한 것이 가장 발근이 빨리 되었으므로 삽목초기에는 낮은 양액농도가 경제적일 것으로 보인다. 생장조절제의 농도별로는 NAA나 IBA 0.01mg/l처리가 효과적이었으며 IBA처리보다는 NAA처리시의 발근소요일이 더 짧았다. 또한 NAA 및 IBA을 처리한 수돗물을 사웅하여 삽수의 발근을 유도할 경우 NAA와 IBA를 삽수에 침지처리한 후 수돗물에 재배하는 것보다 발근에 효과적이었으며, 무엽지삽보다는 유엽지삽이 효과적이었다. 또한 배양액이나 생장조절제를 단용처리한 것보다 배양액과 생장조절물질의 혼용처리가 발근소요일이 단축되었고 생육상태가 양호하였다.

본(本) 실험(實驗)은 벼에 있어서 냉해(冷害)로 인(因)하여 매년(每年) 막대한 수확량(收穫量)의 감소(減少)를 생육시기별(生有時期別) 생장조절제(生長調節劑) 처리(處理)에 의한 재배적(栽培的) 방법(方法)을 통하여 그 피해(被害)를 감소(減少)시키고, 생장조절제(生長調節劑)에 대한 벼의 생리학적(生理學的) 활동(活動)과 농업적(農業的) 특성(特性), 수량구성요소(收量構成要素), 근활력(根活力), Chlorophyll 함량(含量) 등(等)의 변화(變化)를 통하여 수확량(收穫量)에 관계(關係)는 요소(要素)를 규명(糾明)하고, 벼 재배(栽培) 방법(力法)에 있어서 기초(基礎) 자료(資科)로써 이용(利用)하고자 실시(實施)하여 얻은 실험결과(實驗結果)는 다음과 같다. 저온(低溫)조건하에서 처리(處理)된 모든 생장조절제(生長調節劑)는 농도(濃度)에 관계(關係)없이 초장(草長), 분니 등의 벼 생유지연(生有遲延)을 다소 경감(輕減)시켰으며, 특(特)히 ABA는 농도(濃度)에 관계(關係)없이 초장(草長), 분니수등에 있어서 다른 생장조절제(生長調節劑)보다 그 효과(效果)가 두드러진 것을 알 수 있었다. 저온(低溫) 조건하(條件下)에서의 chlorophyll함량(含量)은 무처리구(無處理品)에 비하여 감소(減少)되나 식물생장조절제(植物生長調節劑)를 처리(處理)함으로써 Chlorophyll함량(含量)이 증가(增加)되었고, 또한 근활력(根活力)도 chlorophyll함량(含量)과 같은 경향(傾向)을 나타내었다. 생육(生有) 초기(初期)의 생장(生長) 조절제(調節劑)의 처리(處理)는 수량(收量) 구성요소(構成要素)의 감소(減少)를 경감(輕減)시켜 주었으며, 이는 수량(收量)에 직후(直接) 영향(影響)을 미쳐 냉해(冷害)로 인(因)한 수량감소(收量減少)를 경향(經向)시켰으며, 특(特)히 Abscissic acid처리(處理)의 효과(效果)는 뚜렷하게 나타났다. 그러나 저온하(低溫下)에서 수잉기때 생장조절제(生長調節劑) 처리(處理)는 영양생장(營養生長)에 별다른 효과(效果)를 나타내지 않았으나 수량구성요소(收量構成要素)에는 다소 영향(影響)을 미쳐 수량(收量)에 관여(關與)하는 것으로 나타났다. 저온조건하(低溫條件下)에서의 생장조절제(生長調節劑)의 처리(處理)는 처리시기(處理時期)에 따라 다소 차이(差異)가 있지만 수량손실(收量損失) 경감(輕減)에 크게 영향(影響)을 미친 것으로 사료(思料)된다.

식물생장조절제(植物生長調節劑)에 의(依)한 담배의 액아발생(腋芽發生)에 관(關)한 기초자료(基礎資料)를 얻고자 조생종(早生種)인 hicks와 만생종(晩生種)인 kusaga mammoth에 MH, GA, BA의 농도를(濃度)를 달리해서 단독(單獨) 또는 혼용처리(混用處理) 하였을 시 액아발생(腋芽發生)에 미치는 영향(影響)을 구명(究明)한바 그 결과(結果)를 요약(要約)하면 다음과 같다. 적심(摘心) 직후(直後) MH900g(a.i.)/ha 처리(處理)는 액아발생(腋芽發生)을 완전히(完全)히 억제(抑制)시켰지만 농도(濃度)가 감소(減少)함에 따라 품종(品種)에 관계(關係)없이 액아(腋芽)가 발생(發生)하였다. 무적심(無摘心) 개체(個體)에서도 비슷한 경향(傾向)을 나타내었다. 적심(摘心)한 개체(個體)에서는 GA와 BA의 여느 농도(濃度)에서 혼용(混用)을 하여도 MH가 첨가(添加)되면 액아(腋芽)가 발생(發生)하지 않지만 무적심(無摘心) 개체(個體)에서는 MH 900 g(a. i.)/ha에 BA와 GA의 농도비(濃度比)가 10:1로 혼용(混用)될 때는 액아(腋芽)가 발생(發生)하였다. 무적심(無摘心) 개체(個體)에 GA와 BA 처리(處理)는 액아발생(腋芽發生)에 아무런 영향(影響)을 미치지 않았다. 적심(摘心)한 개체(個體)에 GA와 BA의 단독처리(單獨處理)는 농도(濃度)가 높아짐에 따라 액아발생(腋芽發生)을 증가(增加)시키며 혼용(混用)하였을 때에는 antagonistio한 경향(傾向)을 나타내었다.

Background : Rhododendron brachycarpum belong to Ericaceae family is northern herbaceous plant and grows high in mountains of Korea. Traditionally, this plants have been used to treat arthralgia, neuralgia, hypertension, roborant and diuretic. In spite of medicinal values, natural populations are decresing due to climate change and grows slowly. Therefore it need to secure plant materials and in vitro culture is able to the alternative methods. In this study, we examined the effect of PGRs treatment using leaf and petiole explants. Methods and Results : The effects of the different surface sterilization agents (NaOCl and HgCl2) and time were tested. Best results with lower contamination and higher explants survival were recorded with 2 - 4% NaOCl for 1 minutes and 0.5 - 1.0% AgNO3. Callus was obtained when cultured onto MS medium using different concentration and combination of 2,4-D, BA and NAA. Maxium induction of callus was obtained from combinations of 2.0 ㎎ l-1 2,4-D and 1.0 - 2.0 ㎎ l-1 BA from leaf explants. Petiole explants were more effective to induce callus than leaf explants from combination of 1.0 ㎎ l-1 2,4-D and 0.1 - 1.0 ㎎ l-1 BA. Conclusion : The resultes provide that different explants and PGRs combinations were good source of callus induction.

Background : Korean ginseng require 3 - 4 years to produce mature seeds from their mother plants. Therfore, it takes over 20 years to genetic fixation by artificial crossing of 8 generation. Anther culture is a useful method for obtaining homozygotes in only one generation. However, there is not much research on ginseng yet. In this study, we investigated the callus induction of anther depending on the type and concentration of the plant growth regulators in Panax ginseng C. A. Meyer. Methods and Results : Flower buds of P. ginseng were cold pretreated at 2 days before the anthers were plated on the induction medium. The flower buds were immersed in 70% ethanol for 30 sec min, washed two times with sterile distilled water, surface-sterilized in 2% sodium hypochlorite solution for 20 min, then rinsed five times with sterile distilled water. The anthers were placed on Petri dishes containting fifteen different concentrations and combinations of 2,4-D, NAA, BAP and KT. Callus induction was significantly influenced by the type and combination of plant growth regulators. The highest callus induction rate was observed in GR5 medium at 79.2%. The 2,4-D mediums had significantly higher callus induction than the NAA medium, and 2,4-D 1 ㎎/ℓ have a higher callus induction rate than the other concentrations. The increase of callus induction rate was not observed by the addition of cytokinin, but the callus induction rate was gradually decreased as the BAP concentration was increased. There was no difference in callus induction rate between BAP and KT. Conclusion : The important factor for inducing callus of ginseng anther was the addition of 2,4-D, and no effect of cytokinin addition could be found.

This research was conducted to evaluate methods of enhancing the waterlogging resistance of soybean plant. Thus, we applied seven types of plant growth regulators (PGRs) to soybean plants and exposed them to waterlogged conditions for a total of 14 days. To evaluate stress resistance, we monitored plant growth characteristics data such as height, chlorophyll content, and chlorophyll fluorescence for 28 days after the initial waterlogging (14 days under waterlogging conditions and 14 days after waterlogging). According to the results, plant height was significantly increased by gibberellin A4 (GA4) treatment compared to the control treatment and waterlogging-only treatment. However, we could not detect plant height owing to plant death when we applied abscisic acid (ABA). Except for GA4 and ABA treatments, plant heights slightly decreased in all treatments compared to the waterlogging-only treatment. The chlorophyll content and chlorophyll fluorescence showed a similar tendency among PGR treatments. The chlorophyll content and chlorophyll fluorescence were significantly increased by ethephon and kinetin treatments 28 days after waterlogging compared to the waterlogging-only treatment. Consequently, kinetin and ethephon treatments induced more resistant phenotypes in soybean plants during or after exposure to waterlogging conditions.

Platycodon grandiflorum (Bell flower) is an important plant that has traditionally been used as herbal medicine for the treatment of cough, phlegm, sore throats, lung abscesses, chest pains, dysuria, and dysentery. The present study was initiated to investigate the feasibility of inducing shoot and root organogenesis in cultured explants of P. grandiflorum in a range of culture media and through use of various plant growth regulators (PGRs). The plantlets (Stem containing one node) were isolated and cultured on different concentrations of Murashige and Skoog (MS) medium supplemented with PGRs. We found that proliferation and elongation of shoots and roots could be achieved on ¼ MS for P. grandiflorum with wild and green petals and on ⅛ MS for P. grandiflorum with double petals. The highest levels of development and elongation of adventitious shoots and roots were observed when petal explants were cultured on ¼ MS (pH 3.8) supplemented with 5% sucrose. Increasing the agar concentration reduced shoot growth and rooting potential; nevertheless, the highest number of shoots and roots was observed on 0.6% agar. In the case of growth regulators, ¼ MS supplemented with 1 mg L-1 6-benzylaminopurine (BA) was found to be best for shooting, although higher concentrations of BA tended to reduce shoot and root elongation. The highest number of shoots was achieved on 0.5 mg ․ L-1 thidiazuron (TDZ) from double petal explants grown on ⅛ MS. However, root and shoot elongation were found to decrease when TDZ concentrations were increased. Low concentrations of kinetin, naphthalene acetic acid, indole acetic acid, and 3-indole butyric acid induced shoot and root proliferation and elongation. Taken together, our study showed that low concentrations of PGRs induced the greatest root formation and elongation, showing that the optimal concentration of PGRs for shoot proliferation was species-dependent.

Background : This study was conducted to developed the propagation method by cutting for mass cultivation of Vitex roundifolia. We were pitched the cutting two times and treated plant growth regulators to enhance the rooting percentage. Vitex roundifolia is live in beach sandy soil south of Hwanghae-Do and Gangwon-Do. Vitex roundifolia have been used to bath foam. It is good for aromatic plant. It has 0.8% essential oil content in leaf and flower. Major components of essential oil were alpha-Pinene, Sabinene, beta-Pinen, 1,8-cineole, d-Limone. Despite the superior usability, it had not yet been made by the artificial cultivation Methods and Results : We were pitched the cutting of a first-year branch on June 5, which was greenwood cutting and July 17, which was semi-hardwood cutting at Kwangseung-ri beach, Gochanggun, Jeonbuk. The length of cutting was 10cm. It had 3～4 nodes, we stuck a cutting remain 2 nodes above ground on ordinary raise seedling soil. Rooting percentage was measured at 60 days after stuck a cutting. Rooting percentage was higher greenwoody cutting(95%) than semi-hardwood cutting(57.6%). In green wood cutting, there was no significance with plant growth, but chemical injury was occurred in IBA 5,000ppm. In semi-hardwood cutting, there was significance with plant growth regulators. The rooting percentages of all the treat were higher than control(no treatment). Rooting percentage was the highest in NAA 5,000ppm treated. Conclusion : Greenwood cutting method was more proper to propagation for Vitex roundifolia than semi-hardwood cutting. The optimum time to cutting for Vitex roundifolia propagation was the early in June. If miss a time to propagation Rooting percent was elevated by plant growth regulator.

This study had been conducted to investigate the effect of some plant growth regulators inducing fruit enlargement and optimal harvest time in Sageretia thea. Two hundred fifty ㎎/ℓ mepiquat chloride treatment, 1㎎/ℓ thidiazuron treatment on full bloom, and 200㎎/ℓ gibberellic acid treatment on 7 days before full bloom resulted in the increase of 21.7% in weight, and 200㎎/ℓ gibberellic acid treatment 7 days before full bloom, 10㎎/ℓ forchlorfenuron treatment 14 days after full bloom, and 1㎎/ℓ thidiazuron treatment on full bloom also brought about positive effects on the enlargement of the fruit, increasing 6.3%, 6.3% and 8.1% in its transverse diameter, respectively. Furthermore, the effects of the plant growth regulator treatments on the harvest time of Sageretia thea were determined as follows: the increase in the optimal harvest time of 57.2 - 75.4%, shorter maturation period, by the treatments with 500㎎/ℓ mepiquat chloride 7 days after full bloom, 100㎎/ℓ gibberellic acid treatment on full bloom, 2.5㎎/ℓ forchlorofenuron 7 days after full bloom and 2㎎/ℓ thidiazuron treatment 7 days before full bloom; and the greater effects of plant growth regulator treatments on the fruit maturation in the following order, gibberellic acid > thidiazuron > forchlorofenuron > mepiquat chloride. The results of this study are expected to be used as a reference data to develop Sageretia thea as a new local specific crop for Jeju island.

This study was conducted to improve the postharvest storage techniques of managing and storing seeds, totest qualities and viabilities of the seeds and to examine the germination rate and the protein expression of Achyranthesjaponica Nakai. The seeds collected from different areas of Je-Cheon and Gwang-Ju were stored with different temperaturesand durations. Two plant growth regulators and two seed priming were treated to investigate their effect on the germinationrates and the days required for germination. The weight of one hundred seed collected in Gwang-Ju was heavier than thosein Je-Cheon. Seed length collected in Gwang-Ju was also longer about 5.12㎜ than those in Je-Cheon about 4.90㎜ andseed width was longer in Gwang-Ju than those in Je-Cheon. The rates of seed germination in two different collection areaswere higher about 2.9 to 13.0% in Gwang-Ju compared to those in Je-Cheon. Comparing its rates with the storing tempera-tures and durations, they were not clearly different in between 4℃ and 25℃ and they also were gradually decreased withgetting longer storing durations. The germination rates treated by plant growth regulators were higher with GA3 than thosewith Kinetin. The highest seed germination rate was appeared at 50 ppm of GA3. Comparing its rates with different seedpriming, they were relatively higher with KNO3 than those with PEG6000. In protein expression patterns between before thegerminating and after the germinating of seeds, more and clear bands were appeared in the seed after the germination com-pared to those before the germination of seeds, especially 10~20kDa. These results showing more and clear bands weremore clearly appeared in Gwang-Ju compared to Je-Cheon. Comparing the protein expression with plant growth regulatorsand seed primings, GA3 was better expression than those with Kinetin and KNO3 was better than those with PEG6000. Moreand clear bands were closely related to the germination rates of seeds and more detailed studies would be required.

절화 국화 ‘백설’의 상온 및 5℃ 저장시 Promalin 50mg.L-1 처 리는 절화 후 초기 개화를 억제시키고 품질을 증진시키는 좋은 작 용을 함을 알 수 있었다. 이러한 효과는 상온 저장시 더욱 효과적이 었으며 상품성 손실과 관계되는 생체중 유지에 작용하여 선도유지 에 좋은 전처리제임을 확인할 수 있었다. 또한 Promalin 50mg.L-1 분무 전처리는 절화 국화의 에틸렌 발생을 억제시키는 경향을 나타 내었으며 호흡급등형 패턴을 나타내고 있음을 알 수 있었다.

This study was conducted to investigate the quality of seeds, the germination rates and the days required for germination, to examine the patterns of protein expressions during the germination and to improve the techniques of managing and storing seeds and viability of the seeds of Lithospermum erythrorhizon Sieb. et Zucc. After collecting and harvesting seeds, they were classified to white and brown colors of seed coat through testing their seed size, weight, and quality. The germination rates, the days required for germination, and the protein expressions were examined with different colors of seed coats, storing temperatures and durations by treating the different plant growth regulators and primings. One hundred seed weight of white color was heavier about 1.17 g than those of brown one about 0.81 g. The germination rates in white color of seed coat was higher, 3.05 ~ 5.75%, than those in brown one. Its rates were decreased with getting longer in storage durations. There was no big differences on germination rates between storage temperatures. The plant growth regulator of GA3 and Kinetin was affected to improve the seed germination. GA3 increased the seed germination clearly at 25 ppm level, while kinetin increased it gradually from 25 to 100 ppm levels. In germination by seed primings, PEG6000 made higher germination rate with increasing their levels, whereas KNO3 increased the germination until 100 mM level and then decreased it with 200 mM unlike PEG6000. The protein expressed during the seed germination were appeared more and clearer bands in the seed after germination, especially 20 ~ 30 kDa, compared to those in the seed before germination. These results showing more and clearer bands were positively related to the germination rates which were different by seed colors, storage temperatures and durations, and plant growth regulators and primings.

본 연구는 바이러스 무병묘의 대량 증식을 위한 기초 자료를 얻고자 포도 '자랑' 품종의 신초와 뿌리의 형성 및 생장에 미치는 배지조성물질과 생장조절제의 영향을 구명하고자 수행되었다. 배지의 무기염 농도가 낮을수록 신초의 형성은 많아지는 경향으로, 특히 1/2MS배지에서 신초의 형성 및 생장이 가장 양호하였다. 부정근의 형성은 무기염의 농도가 높아질수록 양호하여 2MS배지에서 부정근의 수가 2.1개로 가장 많았다. Sucrose의 경우, 신초의 형성은 1%, 부정근의 형성은 3%, 생장은 1% 농도구에서 가장 좋았다. 활성탄의 0.05% 첨가에 의해 신초의 생장은 양호했으며, 특히, 부정근의 형성 및 생장에 효과적이었다. '자랑'의 대량 증식을 위한 배지의 pH는 6.8이 가장 적합하여 신초의 마디수와 길이가 각각 3.9개와 1.3 cm로 가장 좋았다. 기내 대량증식에 미치는 생장조절제의 영향으로 BA 1.0 mg/L에서 신초의 생장이 가장 왕성하였으며, NAA 1.0 mg/L에서 절편체당 16.9개의 신초가 형성되어 양호한 결과를 얻었다.

본 연구는 야생 참당귀의 무균묘 확보, 대량생산체계 확립 및 품종개발을 위해 기내발아와 기관유도에 미치는 PGRs의 영향을 알아보고자 실시하였다. 종자발아 실험은 전처리로 GA3 침지시간(0, 24h, 48h, 72h) 및 종자의 처리 방법(대조구, 기계적가상 처리, 표면 메탄올 가열 소독법)을 달리하여 실시하였다. 그 결과 GA3에 침지시키지 않고 메탄올 가열법으로 처리한 종자를 0.5 mg/L GA3가 첨가된 배지에서 가장 높은 발아율(15%)을 보였으나 저조하여 발아율 향상을 위해 초음파(frequency 80 KHz) 및 PGRs(GA3, BA, TDZ)를 처리하였다. 그 결과 초음파 처리 후 메탄올 가열법으로 처리 한 종자를 0.1 mg/L GA3가 첨가된 배지에 치상하여 발아율(60%)을 증진 시킬 수 있었다. 기내 발아된 식물체로부터 기관유도에 미치는 PGRs(2,4-D, NAA, TDZ, BA)의 영향을 살펴본 결과 캘러스 유도는 줄기, 뿌리, hypocotyl을 1.0 mg/L NAA + 0.5 mg/L BA 처리구에 치상하였을 때 높은 유도율을 보였다. 신초와 뿌리유도는 각각 hypocotyl(PGRs 무첨가)과 뿌리(0.1 mg/L NAA 첨가구)에서 효율적으로 분화되었다. 또한 줄기(1.0 mg/L 2,4-D 처리구)와 hypocotyl(0.1 mg/L NAA 처리구) 조직에서 체세포배가 발생되어 MS 기본배지에 계대배양하여 정상적인 식물체로의 육성이 가능하였다. 본 연구를 통해 무균묘 확보 및 대량생산 체계를 확립하였으며 이를 통해 신품종 개발에 유용할 것으로 판단된다.

본 연구는 국내에서 소비되는 약용작물 중 경제적 가치가 높은 백출의 조직배양체계 확립을 위해 수행되었다. 공시재료로는 중국백출(A. macrocephala)과 한국자생백출(A. japonica)의 교잡종인 '다출' 품종의 뿌리와 액아를 이용하였다. 뿌리배양을 위해 BAP, 2-iP, IBA, NAA를 혼용 처리한 결과, 캘러스 유도율은 BAP 처리군에서 다소 높았으나, 캘러스 증식 및 뿌리의 유도에는 2-iP 처리가 효과적이었다. 뿌리조직은 낮은 싸이토키닌의 농도와 높은 옥신의 농도에서 캘러스 유도 및 증식이 원활하였으나 식물체 재분화에는 적합하지 않았다. 백출의 액아배양 시 BAP와 NAA의 혼용처리가 2-iP와 NAA 혹은 IBA 처리보다 재분화식물체 생산에 효과적이었다. 1.0 mg/L BAP와 1.0 mg/L NAA 조건에서 액아 당 신초 출현 수가 3.8개로 가장 많았고, 경직경이 5.0 mm 이상으로 양호하였다. 그러나 BAP를 2-iP로 대치하는 경우 재분화 식물체의 초장은 큰 경향을 보이나 액아 당 재분화 식물체의 수가 적은 것으로 조사되었다. 또한 Sucrose 농도를 70 g/L로 하는 경우 액아로부터 재분화한 식물체의 뿌리 비대에 효과적이었다. 본 실험 결과, 백출의 기내 대량증식을 위한 조직으로는 뿌리보다 액아조직이 효율적이며, 식물의 재분화에는 1.0 mg/L BAP와 1.0 mg/L NAA 적합하고, 고농도의 sucrose가 뿌리 비대에 유용한 것으로 사료된다.

본 연구는 수수의 성숙 종자로부터 캘러스유기 및 재분화 효율 조사하기위하여 수행되었다. 배발생 캘러스 형성을 살펴보기 위해 생장조절제 효과를 조사하였다. 수수 성숙종자로부터 캘러스 유기에 적합한 생장조절제 종류와 농도는 2 mg/L 2,4-D인 것으로 나타났다. 배발생 캘러스의 고효율 빈도는 B5 배지에 2 mg/L 2,4-D을 첨가하였을 때 가장 양호한 것으로 나타났다. 배발생 캘러스로부터 식물체 재분화는 BAP와 IBA를 넣은 MS 배지가 가장 적절한 것으로 나타났다. BAP 농도가 높을수록 신초재분화가 활발하였다. 따라서, 본 연구 결과로부터 수수 기내배양시 신초와 발근 형성에 효과적인 생장조절제 조합은 0.5 mg l-1 BAP와 0.25 mg l-1 IBA인 것으로 나타났다.

반수체 육성은 육종연한을 단축시키기 위해 유용한 도구이다. 본 연구는 밀 품종 조기 육성을 위한 반수체 육종 시스템을 개발하기 위해 반수체 육성시 식물생장조절제 처리가 배 배양에 미치는 영향에 대해서 조사한 것이다. 밀 이삭의 제웅 작업을 수행하고 옥수수와 원연교잡한 후 종자결실은 2,4-D 및 2,4,5-T 150 mg/L, dicamba 50 mg/L 처리에서 가장 좋았으며, 배형성은 2,4-D 및 2,4,5-T 100 mg/L, dicamba 50

This experiment was conducted to examine the influence of four plant growth regulators on growth, photosynthesis parameters and yield of soybean. To increase dry matter accumulation of seeds, some growth regulators were applied to field grown soybean cv. Sinpaldalkong #2 as determinate type and Muhankong as indeterminate type at dense planting condition. Choline caused significant reduction of stem length, but did not increase seed yield. The number of leaf and total leaf area were showed significant increase in all the treatments, but those increased tremendously in Muhankong treated with ethrel. CO2 assimilation and water use efficiency of a single leaf were showed the highest as 17.2 molm-2s-1 and 9.3 μ mmol mol-1 treated with mepiquat in Sinpaldalkong, respectively. The Photosynthetic rate was closely related to stomatal conductance, transpiration and water use efficiency. Mepiquat treatment mainly produced positive effects on the number of pods, percent of pod setting, number of seeds per pod in two cultivars and also increased their seed yield as compared with control.