Earl's Favourite Research Articles

Identification of QTLs for resistance to powdery mildew and SSR markers diagnostic for powdery mildew resistance genes in melon (Cucumis melo L.)

Powdery mildew caused by Podosphaera xanthii is an important foliar disease in melon. To find molecular markers for marker-assisted selection, we constructed a genetic linkage map of melon based on a population of 93 recombinant inbred lines derived from crosses between highly resistant AR 5 and susceptible 'Earl's Favourite (Harukei 3)'. The map spans 877 cM and consists of 167 markers, comprising 157 simple sequence repeats (SSRs), 7 sequence characterized amplified region/cleavage amplified polymorphic sequence markers and 3 phenotypic markers segregating into 20 linkage groups. Among them, 37 SSRs and 6 other markers were common to previous maps. Quantitative trait locus (QTL) analysis identified two loci for resistance to powdery mildew. The effects of these QTLs varied depending on strain and plant stage. The percentage of phenotypic variance explained for resistance to the pxA strain was similar between QTLs (R (2) = 22-28%). For resistance to pxB strain, the QTL on linkage group (LG) XII was responsible for much more of the variance (41-46%) than that on LG IIA (12-13%). The QTL on LG IIA was located between two SSR markers. Using an independent population, we demonstrated the effectiveness of these markers. This is the first report of universal and effective markers linked to a gene for powdery mildew resistance in melon.

秋作温室メロンのロックウール栽培における培養液組成・濃度と養分吸収の関係

Effects of composition and concentration of nutrient solution on the uptake of nutrients by muskmelon (Cucumis melo L. cv. Earl's Favourite) grown in rockwool in the fall were compared with those grown in the spring (Jang and Nukaya, 1997). Muskmelons were supplied full and half strength Enshi solution and full strength of Shizudai solution. Leaf and stem fresh weights were greater at full strength of Shizudai and half strength of Enshi solution than those given full strength Enshi. The plants absorbed more mineral elements (me·plant-1·day-1) and the uptake concentration (uptake ratio of mineral elements to nutrient solution, me·liter-1) were greater at earlier growth stages, and less at later ones in all solutions. The absorption rate tended to be faster at full strength of Enshi solution than with other solutions. Our data reveal that the uptake rate and concentration were similar to those reported in the spring experiment. However, the uptake rate and concentration by the fall crop tended to be slightly lower at earlier stages and higher at later stages compared with those in the spring crop.

Expression of ACC Synthase and ACC Oxidase Genes in Melons Harvested at Different Stages of Maturity.

Melon (Cucumis melo L.) fruits vary in ethylene production rates, depending on the cultivar, which can affect the storability of the fruits. To understand these differences at both the biochemical and molecular levels, two popular cultivars, 'Andes' and 'Earl's Favourite' were used ; these cultivars produce relatively high and low amounts of ethylene, respectively. Ethylene biosynthetic activity in the peel, mesocarp and placenta of 'Earl's Favourite' fruits harvested at different stages of maturity remained low even at the commercial harvest maturity (CHM), and ethylene production in the intact fruit was also low. In 'Andes', 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) activity and ACC content in the mesocarp and placenta and ethylene production in intact fruit increased drastically at CHM. Northern blot analysis using mRNA extracted from the respective tissues of fruits at different stages of maturity indicated that CMe-ACS1 mRNA accumulated in the mesocarp and placenta of 'Andes' at CHM, whereas in 'Earl's Favourite' there was no accumulation in any of the tissues at all maturities. In ACC oxidase (ACO) genes, mRNA for ACO1 accumulated in the mesocarp and placenta of both cultivars at CHM, and that for ACO2 was almost constitutively expressed. Ethylene, exogenously applied to fruits at the preclimacteric stage, slightly induced CMe-ACS1 mRNA accumulation in 'Andes' but not in 'Earl's Favourite' fruits, whereas wounding induced CMe-ACS1 transcripts accumulation in both cultivars. The accumulation of ACO1 mRNA in the two cultivars was greatly stimulated by ethylene and wounding treatments. When 'Andes' fruit at climacteric stage were treated with 1-methylcyclopropene (MCP), an inhibitor of ethylene action, transcripts for CMe-ACS1, ACO1 and ACO2 were barely detectable. These results suggest that the difference in the ethylene-forming capability between the two cultivars may result from the expression of CMe-ACS1 mRNA during natural fruit ripening and in response to exogenous ethylene.

Comparative Analysis for Replication and Movement of Cucumber Mosaic Virus in Cucumis figarei and C. melo.

Replication and movement of cucumber mosaic virus (CMV) in CMV-resistant Cucumis figarei (CF) and a CMV-susceptible melon C. melo cv. Earl's Favourite (EF) were compared. Although EF plants were readily infected with CMV at 1.0μg/ml and developed systemic symptoms, leaves of CF plants inoculated with CMV virions (0.5mg/ml) or CMV RNA (50μg/ml) were locally infected. Infected cells within inoculated CF leaves as observed by confocal laser scanning microscopy were notably confined and did not enlarge over time. The number of infected protoplasts isolated from CMV-inoculated CF leaves was significantly lower than that from EF. The amount of CMV antigen detected by ELISA or western blotting in inoculated CF leaves was about 10-fold lower than that in EF leaves. Both (+) and (-) strands of CMV-specific RNAs were detectable from CF leaves, but the amounts of RNAs 1 and 2 were 500- to 1000-fold smaller and those of RNAs 3 and 4 were 100-fold smaller, than those from EF leaves. Protoplasts prepared from healthy CF were as susceptible as those from EF to infection with CMV or CMV RNA. The amount of CMV antigen in RNA-inoculated CF protoplasts detected by ELISA or western blotting similarly increased with time as did that in EF protoplasts. Although both strands of RNAs 3 and 4 similarly accumulated in protoplasts from CF as well as EF, the amounts of RNAs 1 and 2 in CF were suppressed to 1/5 of that in EF. Symptom expression, serology, infectivity, accumulation of CMV antigen in inoculated plants and RNA profile in CMV virions recovered from the infected CF leaves did not noticeably change from those of the original CMV. These results indicate that CF resistance to CMV may be caused in part by interference with viral replication, but the inhibition of virus movement via both cell-to-cell and long-distance pathways is the primary mechanism.

Isozyme Polymorphism in Melon (Cucumis melo L.), and Application to Seed Purity Test of F1 Cultivars.

Isozyme polymorphism was studied for melon cultivars, in order to identify suitable markers for seed purity test of commercial Fl cultivars of Japanese muskmelon. Intraspecific variation was detected by the analysis of acid phosphatase (APS) isozymes. A total of 108 melon cultivars, covering five varieties of C. melo, was classified into five zymogram types according to APS zymogram. As for pure line cultivars, D type was commonly found in all the varieties, while C type was specific to var. inodorus. F1 cultivars of muskmelon were all classified as A type which was considered to be homozygous at APS Ioci, and thus it was impossible to test seed purity by the analysis of APS isozymes. On the other hand, the analysis of peroxidase (POX) isozymes enabled to classify melon cultivars into three major groups (Px2A, Px2B, and hetero-type). Breeding lines for disease resistance belonged mostly to the Px2A type, and pure line derivatives of a high fruit quality cultivar ‘Earl's Favourite' were all classified as Px2B type. It was thus suggested that the demand for both fruit quality and disease resistance resulted in the breeding of hetero-type cultivars, which accounted for half of the F1 cultivars. For hetero-type cultivars, it is possible to detect the contamination by selfed seeds of the female parent by the analysis of a single POX marker, and it takes only nine days for analyzing seed samples. Purity test for seed samples of four commercial F1 cultivars showed that contamination sometimes occurred at a low frequency. The results clearly indicated that this method is practically applicable to seed purity test for many cultivars of Japanese muskmelon.

Purification and Some Properties of a Protease from the Sarcocarp of Musk Melon Fruit.

A protease has been purified from sarcocarp of musk melon, Cucumis melo ssp. melo var. reticulatus Naud. Earl's Favourite. The protease was mostly present in the placenta part of the fruit and next in the inside mesocarp. The molecular mass of the enzyme was estimated to be about 62kDa on SDS-PAGE. The enzyme had a carbohydrate moiety. The optimum pH of the enzyme was 11 at 35°C using casein as a substrate. The enzyme was stable between pH 6 and 11. The enzyme was strongly inhibited by diisopropyl fluorophosphate, but was not inhibited by EDTA or cysteine protease inhibitors. From the digestion of Ala-Ala-Pro-X-pNA (X = Phe, Leu, Val, Ala, Gly, Lys, Glu, Pro, and diaminopropionic acid (Dap) substrates the specificity of the protease was found to be approximately broad, but the preferential cleavage sites were C-terminal sites of hydrophobic or acidic amino acid residues at P, position. It was proved that the enzymatic properties of musk melon protease are similar to those of cucumisin [EC 3.4.21.25]. The enzyme was not inhibited by typical proteinous inhibitors such as STI or ovomucoid. Therefore, this enzyme seems to be a useful protease for the food industries.

温室メロンのロックウール栽培における培養液濃度と養分吸収の関係

Summary The relationship between nutrient concentration and uptake of nutrients by muskmelon (Cucumis melo L. cv. Earl's Favourite) grown in rockwool was studied to determine mineral absorption characteristics. Muskmelons were supplied one-third, two-thirds, and full strength Enshi solution. Leaf and stem fresh weights were markedly reduced when the plants were grown in one-third strength. Fresh weight and soluble solids content of fruits were highest in plants grown in full strength, followed by two-thirds, and one-third strength, respectively, but there were no distinct differences in their external appearance. During the early growth stages, the uptake rate of mineral elements (me/plant day) and the uptake concentration (uptake ratio of mineral elements to nutrient solution, me/liter) were highest in plants grown in full strength, followed by two-thirds, and one-third strength, respectively, but the uptake rate and concentration did not differ among treatments during growth after pollination. These results suggest that in rockwool culture of muskmelon, maintaining a higher nutrient concentration until pollination or pinching results in higher yield and quality of fruit. Furthermore, these findings also suggest that mineral concentration in the root environment is not as critical to nutrient uptake and fruit production at later stages.

Formation of alcohol substances in muskmelon: variation among cultivars and with maturity

To elucidate the differences in the formation of alcohol substances between different cultivars of muskmelon ( Cucumis melo L.), 24 cultivars were tested for alcohol substance concentration (ASC) in the flesh and inner tissue of the fruit. The change in ASC with maturity was also investigated. Of the 24 cultivars tested, four showed markedly high ASC in every crop and two cultivars occasionally showed markedly or fairly high ASC. These cultivars were of ‘Earl's Favourite’ or ‘Earl's Favourite’ and ‘British Queen’ ( C. melo var. reticulatus) parentage, with most falling into the latter category. An exception was ‘Prince’ which was an F 1 hybrid of ‘Charante’ (var. reticulatus) and var. acidulus. Cultivars belonging to var. inodolus or acidulus and their F 1 hybrid showed consistently low ASC. High ASC was found only in the inner tissue of the fruit, not in the flesh. ASC in the inner tissue began to increase from 10–15 days before the fruit reached maturity for shipment and continued to increase for the first 10 days of after-ripening at 20°C.

Squash Mosaic Virus Isolated from Melon (Cucumis melo L.) in Hokkaido

Squash mosaic virus (SMV) was isolated from a melon (Cucumis melo L. var. reticulatus) showing mosaic symptoms in Yuhbari, Hokkaido. The host range was limited to Cucurbitaceae, except for Pisum sativum and Lathyrus odoratus, among 41 plant species belonging to 10 families tested. The virus was not transmitted by the aphids, Myzus persicae and Aphis gossypii, but transmitted by the chrysomelid beetles, Aulacophora femoralis and Atranchya menetriesi, and coccinelled beetles, Epilachna admirabilis and E. sparsaorientalis. When the insects, A. femoralis and E. sparsaorientalis, were transferred daily to healthy melon plants, they remained infective for 16 days and 4 days, respectively. The percentage of transmission through seeds of melons, cv. Yuhbari King, Earl's Favourite, Honeydew, Spicy, and Prince, and pumpkin (Cucurbita maxima), were 13.5%, 0.5%, 1.0%, 15.3%, 10.7%, and 2.0%, respectively. No seed transmission occurred in pumpkin (Cucurbita moschata), cucumber, and watermelon. Infectivity of crude sap from infected melons was lost by heating at 65-70C for 10minutes, by diluting 2×10-5-10-5, and by aging at 20 C for 12 days. The virus was isometric particles of 25 to 30nm in diameter. In ultrathin sections of the virus-infected melon leaves, the virus particles were observed in the vacuoles of spongy parenchyma cells and palisade parenchyma cells. The tubular structures were observed in the cytoplasm of spongy parenchyma cells and palisade parenchyma cells. The titer of antiserum to the virus was 1: 1600 in the ring interface tests. The antiserum reacted with four isolates of SMV from Hokkaido and an isolate from Okayama, but not with cucumber mosaic virus (CMV) and muskmelon necrotic spot virus (MNSV) in gel diffusion test. From the results, the virus was identified as a strain that belongs to group I of squash mosaic virus. Within 72 samples of diseased melons showing mosaic symptoms, collected in the fields of Hokkaido from 1970 to 1975, 6 different viruses were recovered. They are 47 of CMV, 11 of watermelon mosaic virus, 5 of SMV, 3 of cucumber green mottle mosaic virus, 5 of MNSV, and 1 of tomato ringspot virus.

Studies on the absorption of nutrient elements in muskmelon. IV

1. The aim of the present study is to find out some relation between nutritional accumulation and growth of muskmelon (var. Earl's Favourite) grown under the experimental condition reported in the previous papers. The design of fertilizer treatments is presented in Table I. The results obtained are shown in Tables 2 to 8 and in Figures 1 to 6. 2. Plant height increased rapidly during the five weeks after planting, and then remained constant until harvesting time. The greatest increasing Tate in fruit weight was observed between the second and third weeks after pollination when the fruit net appeared, while there was a great increase in soluble solids in fruit during the two weeks before harvesting time. 3. The amounts of nitrogen in whole plant increased up to the ninth week after planting, and then remained constant until harvesting time. The amounts of nitrogen in leaf increased rapidly during the five weeks after planting, and then slowly during the following four weeks, but decreased thereafter until harvesting time. Those in stem were less than those in leaf, while the accumulation processes in stem were analogus to those in leaf. On the other hand, its accumulation in fruit increased linearly throughout the entire growing period. From these results, it was found that a part of nitrogen in leaf and stem translocated from these organs to fruit during the two weeks before harvesting time. 4. The amounts of phosphorus in whole plant increased up to harvesting time. The amounts of phosphorus in leaf at the standard and low levels of nitrogen increased rapidly between the third and fifth weeks after planting, and then increased slowly until harvesting time, while those of the latter increased slowly between the third and seventh weeks after planting, and then remained constant until harvesting time. The accumulation processes in stem were analogus to those in leaf. On the other hand, the accumulation in fruit increased almost linearly throughout the entire growing period. 5. The amounts of potassium in whole plant increased in almost a linear pattern between the third and ninth weeks after planting, and then increased slowly until harvesting time. The amounts of potassium in leaf and stem increased up to the ninth week after planting, and then remained constant until harvesting time. On the other hand, its accumulation in fruit increased almost linearly throughout the entire growing period. 6. The amounts of calcium were greater in leaf than any other organs of plant and the accumulation in leaf showed almost a linear increase throughout the growing period. Moreover, decreased supply of nitrogen to the plant resulted in greater accumulation and percentage of calcium in leaf. 7. The amounts of magnesium were greater in leaf than in any other organs and those at the standard level were greater in leaf than those of other levels throughout the growing period. The amounts of magnesium in leaf increased up to the ninth week after planting, and then increased slowly until harvesting time. Moreover, magnesium accumulation in whole plant were analogus to that in leaf. 8. The accumulation ratios of phosphorus to nitrogen (100) in leaf and whole plant were about 30 to 50 throughout the entire growing period; those of potassium, calcium and magnesium to nitrogen increased rectilinearly up to fruit harvesting time. On the other hand, the highest ratio of all other elements to nitrogen in fruit was observed between the second and third weeks after pollination when the fruit net appeared. 9. The amounts of N, P2O5, K2O, CaO and MgO in whole plant, at the low level which received ammonium sulphate and at the standard level which received rape-seed cake as nitrogen source were as follows. Those of the former were 6.2, 2.6, 18.5, 15.5 and 2.2g; those of the latter were 7.6, 3.1, 20.5, 17.2 and 3.5g per plant.

Studies on the absorption of nutrient elements in muskmelon. II

The purposes of the present study were to determine what levels and what proportions of the elements, nitrogen, potassium, calcium and magnesium, might best and most economically satisfy the nutritional need of muskmelon plants. Plants of, the Earl's Favourite variety were grown by the method reported in the previous paper. Details of the design of fertilizer treatments are presented in Table 1. The results obtained are presented in Tables 2 to 7, inclusive. These data can be summarized as follows. 1. The main effects of nitrogen were to inhibit vigorous growth, to decrease the leaf, stem and fruit weights, to depress soluble solids and external appearance, to lower the pH value of soil, to depress the nitrogen, phosphorus, potassium, calcium and magesium amounts in the whole plants, and to increase the percentage of nitrogen in various organs of the plant. 2. The main effects of potassium were to inhibit vigorous growth, to depress soluble solids, to lower the pH value of soil, to increase the potassium amount in the whole plant, to decrease the nitrogen and calcium amounts in the whole plant, and to increase the percentage of potassium in various organs of the plant. 3. The main effects of calcium were to promote vigorous growth, to increase the leaf, stem, root and fruit weights, to improve soluble solids and external appearance, to increase the pH value of soil, to increase the nitrogen, phosphorus, potassium, caclium and magnesium amounts in the whole plant, and to increase the percentage of calcium in various organs of the plant. 4. The main effects of magnesium were to depress soluble solids, to lower the pH value of soil, to increase the phosphorus and magnesium amounts in the whole plant, to decrease the calcium ammount in the whole plant, to increase the percentage of magnesium in various organs of the plant, and to decrease the percentage of calcium in various organs of the plant. 5. The interactions of nitrogen and potassium were to decrease fruit weight, and to decrease the nitrogen, phosphorus and potassium amounts in the whole plant. 6. The interactions of nitrogen and calcium were to increase the root weight, to improve soluble solids, to lower the pH value of soil, and to decrease the phosphorus, potassium and calcium amounts in the whole plant. 7. The interactions of calcium and magnesium were to increase phosphorus and potassium amounts in the whole plant, and to decrease the calcium and magnesium amounts in the whole plant. 8. Very few secondary interactions were obtained from the variables. 9. The plants, which received 7g of N, 10g of K2O, 40g of CaO and 0g of MgO per plant were able to maintain vigorous growth and produced fruits of high quality. The results seem to indicate that these amounts are recommendable for the muskmelon culture. 10. The amounts of N, P2O5, K2O, CaO and MgO in the whole plant that received 7g of N, 10g of K2O, 40g of CaO and 0g of MgO were 4.4, 1.6, 6.8, 9.3 and 1.2g respectively, per plant.

Studies on the absorption of nutrient elements in muskmelon. III

The purposes of the present study were to in-vestigate the effect of nitrogen and calcium forms on the fruit quality and the absorption of nutritional elements in muskmelon. The levels of calcium were also investigated. Plants of the variety Earl's Favourite were grown by the method reported in the previous paper. Details of the design of ferti-lizer treatment are presented in Table 1. The re-sults obtained are presented in Tables 2 to 7, inclu-sive. 1. The main effects of increasing the level of calcium were to promote the vigorous growth, to increase the leaf, stem and fruit weights, to im-prove the external appearance, to increase the pH value of soil, to increase the nitrogen, phosphorus. calcium and magnesium amounts in the whole plant, to increase the percentage of calcium in various organs of the plant, and to decrease the percentage of nitrogen in leaves, stem and roots. 2. The main effects of nitrogen form were: NO3-N form increased the fruit weight, increased the pH value of soil, inhibited the vigorous growth, decreas-ed the nitrogen and potassium amounts in the whole plant, increased the calcium amount in the whole plant, and decreased the percentage of nitro-gen in various organs of the plant. 3. The main effects of calcium form were: CaCO3 form increased the nitrogen, phophorus, potassium and calcium amounts in roots. 4. Some interactions were obtained from the variables. 5. No significant effects were shown by any of the nitrogen and calcium forms on the growth and fruit quality. 6. The plants which received 40 to 80g CaO per plant were able to maintain vigorous growth and produced fruits of high quality. Judging from these results, the recommendable amount of calcium application is 40 to 80g per plant. 7. The amounts of N, P2O5, K2O, CaO and MgO in the whole plants resulting from receiving 40 to 80g calcium were 4.8 to 4.9, 2.4 to 2.5, 8.7 to 8.9, 10.1 to 10.7 and 1.6 to 1.7 g per plant, respec-tively.

Studies on the absorption of nutrient elements in muskmelon. I

The purposes of the present study were to deter-mine at which of three levels and in what propor-tions the elements, nitrogen and phosphorus, might best and most economically satisfy the nutritional needs of plants. Muskmelons (var. Earl's Favourite) were planted in 451 boxes each filled with 27 kg paddy soil in the greenhouse on May 6, 1956. To keep the aer-ation for the roots in a favourable condition, 1.5 kg rice straw was used in the bottom of each box. The plants were topped at the 20th leaf on the main stem. The design of fertilizer treatment is presented in Table I. The fruits were set at the 10th node and har-vested approximately 50 days after pollination. The plants were divided into leaves, stem and roots, and these organs were immediately dried in an oven at 65°C and ground with a Wiley Mill to pass a 40 mesh sieve. At the same time the fruits were divided into flesh and seeds, and a wedge from each flesh was removed for chemical analysis. All the data were subjected to variance analysis. The results obtained here are presented in table 2 to 7, inclusive. The results from these data can be sum-marized as follows. 1. The main effects of increasing the levels of nitrogen were to depress soluble solids and the external appearance, to increase nitrogen amounts in the whole plants, to decrease the leaf, stem and fruit weights, and to decrease the potassium, cal-cium and magnesium amounts in the whole plants. 2. The main effects of increasing the levels of phosphorus were to promote the vigorous growth, to increase the fruit and seed weights, to increase nitrogen, phosphorus and potassium amounts in the whole plants, to depress soluble solids, and to im-prove the external appearance. 3. The interactions of nitrogen and phosphorus were observed in nitrogen, potassium and magnesi-um amounts in the whole plants. 4. The plants which received 12g of N and 18g of P2O5 per plant were able to maintain vigorous growth and produced fruits of hign quality. From the results, these amounts seem to be recommend-able for the muskmelon culture. 5. The amounts of N, P2O5, K2O, CaO and MgO in the whole plant received 12g of N and 18g of P2O5 were 6.2, 2.0, 9.7, 4.6 and 1.1 g per plant, respectively.

Studies on the sex expression of flowers in Cucumis Melo L. (I)

Experiments have been continued to investigate the sex expression in Cucumis Melo L. In the present paper, the structure of flower and the inheritance of andromonoeciousness versus monoeciousness are described, and the result of comparison as regards function of pollen from either hermaphroditic or staminate flower is presented. The andromonoe-cious plant used in the experiment was commercial variety Earl's Favourite which represents C. Melo L, var. reticulatus, and for the monoecious plant No. 111 and No. 981, collected in Afghanistan and Pakistan by the Japanese expedition in 1955 were used, of which No. 111 is believed to belong to the snake melon, C. Melo L. var. fLexuosus (Fig. 1). The results obtained are summarized as followes. 1. The hermaphroditic flower on andromoneci-ous plant bore the pistil and the stamens filled with pollen, while the pistillate flower on monoe-cious plant bore the pistil and the rudimentary stamens (Fig. 3, 4). 2. Though there was a fare occurrence of the andromonoecious plant bearing pistillate flower and of the monoecious plant bearing hermaphroditic flower, it was confirmed that the monoeciousness differed from the andromonoeciousness in a single dominant allele (Table 1. 2). 3. Pollen grains of the hermaphroditic flower as well as those of the staminate flower within the same vine germinated on the artificial media (1 agar, 5% sucrose and pH 6. 5) in different degree. The difference of germination percentage of the pollen of hermaphroditic and staminate flower was significant at 5 per cent level, i.e. 75.8 per cent and 66. 2 per cent respectively after one hour of culture. No significant difference was shown in the elongation of pollen tubes, and moreover, the rate of normal pollen was as high as 95 per cent or more in either hermaphroditic or staminate flower (Table 3). 4. Either through the intra self pollination or through the neighbour pollination with pollen of staminate flower within the same vine, the yield and the market value of the mature fruit from hermaphroditic flower were the same. Comparing the character of hermaphroditic flower with those of staminate flower, no significant difference was found with regards the function of pollen, i.e. the rate of fruit setting, the number of germinable seed, and the weight of fruit or seed. From the results, it is suggested that the intra self pollination on hermaphroditic flower facilitates practical procedure of pollination, with an advantage of securing the strict inbred seed.