CUCURBITACEAE 2018 Abstracts (PQ)

Production and Quality

View abstracts in the conference PDF booklet.

Green Nanotechnology: An Effective Approach for Watermelon Growth while Maintaining Quality

Pratibha Acharya, Guddadarangavvanahally Jayaprakasha, Kevin Crosby, John Jifon, Bhimanagouda Patil
Texas A&M University, Vegetble and Fruit Improvement Center, Department of Horticultural Sciences, College station, TX, USA

Nano-priming is an innovative technique for improving seed germination and growth. The present study demonstrated a synthetic process that involves the production of spherical silver nanoparticles (AgNPs) by treating aqueous onion juice with silver nitrate. No ‘‘man-made’’ chemicals other than the silver salt was used in the green nanotechnological process and characterized using ultraviolet-visible (UV-Vis) spectroscopy, dynamic light scattering (DLS) techniques, X-ray diffraction (XRD) and transmission electron microscopy (TEM). Similarly, turmeric oil nanoemulsion (TurNE) was prepared by dropwise reduction method using curcumin removed turmeric oleoresin (CRTO). AgNPs and TurNE were used for priming two varieties of watermelon (Riverside and Maxima) for 12 hr and compared with the unprimed control seeds. Internalization of silver (Ag) in watermelon seeds after treatment with AgNPs was determined by Neutron Activation Analysis (NAA). Germination and emergence tests were conducted in an incubator and greenhouse, respectively, where significant enhancement was observed in treated seeds compared with the unprimed seeds. Seedlings grown in the greenhouse were transplanted at four different locations across Texas: Edinburg, Pecos, Grapeland, and Snook. At 40-days after transplanting (DAT), vine length and stem thickness were found to be significantly higher in AgNPs treated watermelons for both varieties at all locations. Results show that AgNPs priming of seed has potential to decrease production costs of watermelon by enhancing seed germination and plant growth. However, no consistent changes in nutritional levels were observed in watermelon fruits. Lycopene level in the treated fruits of both varieties was observed to be similar to the control watermelons in most of the locations. Our results demonstrate that naturally occurring plant extracts can be used in the production of biocompatible nanoparticles thus paving the way for future application in germination and growth of watermelon without deteriorating the nutritional quality. This study was supported by Research award # SC-1607-013 from Texas Department of Agriculture.

Recent Progress of Cucurbit Grafting in China

Zhilong Bie
Huazhong Agricultural University, Wuhan, China

The earliest literature about vegetable grafting in China was recorded in an ancient book “Fan- Sheng-Zhi-Shu” in the first century, BC. However, commercial grafted vegetable production began in the 1970s. The main purposes of grafted cucurbit production in China are to overcome soil-borne diseases and increase resistance to abiotic stress. In recent years, commercial  grafted cucurbit seedling production developed rapidly in China, which is now the largest country that produces grafted cucurbit seedlings in the world. There are about 3000 companies producing grafted seedlings in China and distribute in different provinces. The facilities and equipment related to grafted seedling production also developed very quickly, including greenhouse, plug trays, automatic seedling machine, substrate production, and environmental controlling systems. There are about 30 cultivars of rootstock that have been bred and  released, especially for the rootstocks of cucumber and watermelon. Recent research on vegetable grafting method, grafting and fruit quality, grafting and abiotic stress, rootstock-scion interaction will be presented and discussed.

Maximizing Internal Quality of Butternut Squash (Cucurbita moschata) through Harvest Timing and Storage

Travis Birdsell¹, Jonathan Schultheis², Penelope Perkins-Veazie³
¹NC Cooperative Extension, Jefferson, NC, USA. ²Department of Horticultural Science, North Carolina State University, Raleigh, NC, USA. ³Plants for Human Health Institute, Department of Horticultural Science, North Carolina Research Campus, North Carolina State University, Kannapolis, NC, USA

While yield is a critical factor when producing a crop, quality is needed to market the crop. The primary goal of this study was to examine soluble solid and nutrient content in butternut squash at stages of fruit development and after subsequent storage. The test was conducted in Salisbury, in the Piedmont region of North Carolina. A randomized complete block design with four replications utilizing ‘Butterfly’ was direct seeded on 26 May 2016. Plants were spaced 0.61 m in-row with 3.04 m between rows on black plastic mulch with drip irrigation. Fruit set was coordinated for 48, 55, 62, and 69 days after seeding (DAS). Fruit were harvested at maturity intervals of 14, 21, 28, 35, and 42 days after anthesis (DAA) and stored for 0, 5, and 9 week periods at 13° C and 70% RH. At the end of the storage period, fruits were sampled for soluble solids (SSC), carotenoids, flesh color, and weight loss. SSC increased significantly between 21 and 28 DAA and slightly between 28 and 35 DAA. Alpha carotene reached a maximum content on the vine at 35 DAA. Carotenoids and SSC did not increase significantly from 35 to 42 DAA and did not decrease during the 5 to 9 week storage period. Maximum values were obtained in squash that were set at 55 DAS, harvested at 35 DAA and stored for 5 weeks with SSC of 11.6, alpha carotene of 1034.09 mcg/100g fwt and beta carotene of 1937.58 mcg/100g fwt. At 0 to 5 weeks storage, β-carotene increased significantly. The above results indicated that in order to maximize both soluble solid content and provitamin A relatives, butternut squash should be harvested 35 DAA and stored for a minimum of 5 weeks when grown in the warm climates of central North Carolina. Partial Funding provided by the Specialty Crop Block Grant Program at the U.S. Department of Agriculture (USDA) through Grant 14- SCBGP-CA-0006 (The CucCAP Project)

Phloem Unloading and Intracellular Transport of Carbohydrate in Developing Melon Fruit: A Global Transcriptional View of Sugar Transporters Responsible for Sucrose Accumulation

Jintao Cheng, Suying Wen, Baiyi Lu, Xiangwei Zeng
Huazhong agricultural university, Wuhan, China

Sugar accumulation in melon fruit has a metabolic transition during its development and leads to high sucrose concentration in the mature fruit. However, it remains unclear whether the phloem unloading pathway alters to adapt to the transition and which sugar transporters are involved in this process. The transport of the phloem-mobile symplasmic tracer carboxyfluorescein (CFDA), a global transcriptional view of four sugar transport relative gene families and functional identification of one tonoplast sugar transporter (CmTST2) were studied during the development of melon fruits. CFDA experiment result indicated that carboxy fluorescein was released from the functional phloem strands during the early and middle stages of fruit development, whereas the symplasmic tracer was confined to the phloem strand during the late stage. This reveals a shift of phloem unloading from symplasmic to apoplasmic pathway during fruit development. In addition, the expression of two sucrose transporter (SUT/SUC) genes, three sugar will eventually be exported transporter (SWEET) genes and one tonoplast sugar transporter gene (CmTST2) are increased around the onset of ripening and sucrose accumulation, while the expression of two cell wall invertase genes, two SWEET genes, three hexose transporter genes, and one tonoplast sugar transporter gene (CmTST1) are decreased. These results provide further evidence for an operation of the apoplasmic unloading pathway after onset of ripening. Furthermore, overexpression of the CmTST2 gene in strawberry and cucumber fruits can increase sucrose, fructose, and glucose accumulation in fruit. These results indicated that sucrose accumulation to a high level in ripening melon fruit need a more strong unloading pathway (apoplasmic) to unload and transport the sucrose to the flesh cells and then to the vacuoles for storage.

Melon Texture Diversity: Sensory and Physical Assessments

Macarena Farcuh¹, Bill Copes², Gaelle Le Navenec3, Cecilia Chi-Ham², Ian Thompson¹, Kent Bradford¹, Dario Cantu¹, Allen Van Deynze¹
¹University of California Davis, Davis, USA. ²HM Clause, Davis, USA. ³HM Clause, La Bohalle, Angers, France

Melon (Cucumis melo L.) is a commercially important horticultural crop worldwide that  presents extensive phenotypic and genetic variation. Texture is one of the key attributes defining melon fruit quality and overall consumer acceptance. The aim of this research was to develop rapid phenotyping tools to characterize differences in texture among a diverse panel of melon varieties during ripening throughout postharvest storage. Texture-related physical and sensory measurements were compared to assess their correlations. We compared eight melon varieties with diverse textural characteristics using sensory (taste panel) and physical (texture analyzer) evaluations and correlated the obtained results. Fruits from each variety were harvested at optimal commercial harvest and stored for six days at 5°C plus one day at room temperature, during two production seasons. Our results show that both methodologies detected significant and reproducible differences in texture among the eight assayed melon varieties. Furthermore, texture-related sensory attributes of firmness, crunchiness, and juiciness significantly correlated with several parameters obtained through the physical assessment of texture by using different probes of the texture analyzer instrument. These results indicate that selection of texture-related attributes in breeding programs targeting overall fruit quality improvement could be accelerated significantly with the application of high- throughput physical measurements to select for phenotypes that highly associate with consumer perception.

Effect of Ethrel and Gibberellic Acid on Sex Expression and Seed Production of Snake Gourd, Trichanunium anguna L.

Muhammad Ghani¹, Abdul Rehman¹, Muhammad Jahangir¹, Imran Khan², Tanveer Ahmad³
¹Institute of Horticultural Sciences, University of Agriculture Faisalabad, Faisalabad, Punjab, 38040, Pakistan. ²Department of Agronomy, University of Agriculture Faisalabad, Faisalabad, Punjab, 38040, Pakistan. ³Department of Horticulture Sciences, Ghazi University, DG Khan, Punjab, Pakistan

Snake gourd (Trichanunium anguna L.) belongs to Cucurbitaceae family and it is cultivated all over the world. It is consumed as fresh vegetable which due to its high nutritional value. Cucurbit plants bear more male flowers than female flowers. If the temperature rises high, pistillate flowers decreases and male flowers increase, and as a result yield is decreased. The yield of the plant is increased by increasing the number of pistillate flowers. The plant growth regulators ethrel and giberellic acid increased pistillate flowers with different concentrations, resulting in increased fruit yield and seed production of cucurbits. GA3 at the rate of 50 ppm significantly increased the plant height, maximum seedling fresh weight, number of male flowers per plant, male-to-female flowering ratio, fruit size, germination percentage, seedling dry weight, plumule length of seedling, radical length of seedling, weight of seeds, and days to first female flower. GA3 at the rate 10ppm of maximized number of fruit per plant and number of seeds per plant. GA3 at the rate 30 ppm maximized the length of fruit. Ethrel at the rate of 250ppm recorded maximized fruit diameter and number of female flowers per plant.

Challenges and Opportunities for Grafted Cucurbit Plants in the United States

Richard Hassell
Clemson University CREC, Charleston, SC, USA

Grafting cucurbits vegetables has been going on in the world for over 60 years. However, grafting in the United States is just starting to happen. The need has never been greater due to the increase in soil borne diseases. Unfortunately, the main reason for this delay in the United States is associated mainly with cost. Grafting is both labor intensive and with the lack of skilled labor force inadequate. Currently the cost of cucurbit grafted transplants is four to five times the cost of a normal transplant. Our research has been focused on bringing these costs down. Things that will be discussed are: 1. The availability of rootstock material; focusing on the pros and cons of each type and what regions in the world they are grown. 2. The release of a new USDA-ARS rootstock, ‘Carolina Strongback’, and effects it may have on the world market. 3. The treatment of the rootstock to prevent re-growth both in the greenhouse, as well as the field. I will discuss the effects on the rootstock and ways to totally eliminate the need for at least one cotyledon on the rootstock (a standard practice with cucurbit grafting) and the ease of making grafting automated. 4. Growing grafted plants in an artificial environment to reduce the overall cost of growing both scion and rootstock material. We are looking at developing a cookbook type system, so that we are not dependent on the constant changing outside environment. We have converted two shipping containers into grow rooms and a healing chamber for this purpose. 5. Finally the effects grafting has on melon fruit; quality and quantity which can be both beneficial and determinable if one does not understand these effects.

Comparative Transcriptome Analysis Reveals Key Genes Potentially Related to Soluble Sugar and Organic Acid Accumulation in Watermelon

Lei Gao, Shengjie Zhao, Xuqiang Lu, Nan He, Hongju Zhu, Junling Dou, Wenge Liu Zhengzhou Fruit Research Institute, Zhengzhou, China

Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the watermelon cultivar 203Z was used as recurrent parent, has spherical fruits with a green rind, dark green pencil stripes at the mature fruit stage, pink red flesh, a high total soluble sugar content, and a low total organic acid content. The wild watermelon PI 271769, which was the donor parent, has spherical fruit with pale green, a low total soluble sugar content and a high total organic acid content with white flesh at the mature fruit stage. Near-isogenic line (NIL) SW (in the ‘203Z’ background) with a sweet and sour flavor was developed by backcrossing 7 times and self-pollinating 4 times. Then ‘203Z’ and SW were used as experimental materials for measuring the soluble sugars and organic acids and performing comparative transcriptome analysis. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD- cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

Fungicide Resistance Occurrence Determined for Cucurbit Powdery Mildew (Podosphaera xanthii) and Downy Mildew (Pseudoperonospora cubensis) using a Seedling Bioassay

Margaret McGrath¹, Beth Gugino², Andrew Wyenandt³, Kathryne Everts4, Jake Jones4
¹Cornell University, Riverhead, NY, USA. ²The Pennsylvania State University, University Park, PA, USA. ³Rutgers University, New Brunswick, NJ, USA. 4University of Maryland, Salisbury, MD, USA

Effectively managing downy and powdery mildew in cucurbit crops in the US necessitates applying fungicides with high risk for resistance development. A seedling bioassay was used to examine fungicide sensitivity in Maryland, New Jersey, New York, and Pennsylvania in 2016-18. Plants at about the 2-leaf stage were sprayed with various fungicides at high and low or half label rates, exposed to natural pathogen populations by placing them next to field-grown plants with one of these diseases for up to 2 days, then kept in a greenhouse until symptoms developed and severity was compared to nontreated plants. In 2017 bioassays for Podosphaera xanthii, thiophate-methyl (FRAC code 1) and trifloxystrobin (11) were ineffective likely due to resistance at all locations where the bioassay was conducted. Boscalid (7) was ineffective in NY and moderately effective in NJ and PA. Cyflufenamid (U6) was moderately effective in NJ and effective in NY and PA. Myclobutanil (3) was effective in all assays but in NJ it was only moderately effective at low label rate. Quinoxyfen (13), metrafenone (U8), and fluopyram (7) were highly effective at all locations. Results were more variable with bioassays for Pseudoperonospora cubensis. Azoxystrobin (11) was ineffective likely due to resistance at all locations. Fluopicolide (43) and mandipropamid (40) were also ineffective in NY whereas fluopicolide was effective in PA and MD. Dimethomorph (40) exhibited moderate efficacy in NY and PA. Cymoxanil (27) also exhibited moderate efficacy in NY and in PA at one location; it was highly effective in the other location in PA and in MD. Propamocarb hydrochloride (28) was ineffective at low rate but moderately effective at high rate in MD and PA whereas it was highly effective at both doses in NY. Ametoctradin (45) formulated with dimethomorph was also ineffective at the low rate in PA but only at one location whereas it was moderately effective in MD and highly effective at both doses in NY. The most effective fungicides were zoxamide (22) formulated with chlorothalonil (M5), chlorothalonil, cyazofamid (21), and oxathiapiprolin (U15). Knowing when resistance impacts fungicide efficacy is critical for determining which fungicides to use.

Performance of Pumpkin Lines Bred by World Vegetable Center in Different Highland Areas of Thailand During the Winter Season

Nittaya Nokham¹, Nuengruethai Boonmala¹, Kasemsan Arsakit¹, Pedcharada Yusuk¹, Narinder P.S.Dhillon²
¹Highland Research and Development Institute (Public Organization), Chiangmai, 50200, Thailand. ²World Vegetable Center, East and Southeast Asia/Oceania, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, 73140, Thailand

Pumpkin is one of the most widely grown crops worldwide with immense economic potential and nutritional importance. Performance of cultivars is influenced by environments. The objective of this study was to evaluate the performance of three pumpkin lines bred by World Vegetable Center (AVPU1502, AVPU1504, AVPU1505), along with the local commercial check cultivar (Deliga), in different highland areas of Thailand in the winter season: Location 1- Royal Park Rajapruek, Muang Chiang Mai (200 meters above sea level, Location 2 – Royal Agricultural Station, Pangda (500 meters above sea level; Location 3 – Royal Agricultural Station, Anghang (1,000 meters above sea level). Plot size was a 5 m-wide bed with one 16 m-long row per bed (15 plants). Entries were replicated 3 times and plots were arranged in a randomized complete block design. In Location 1, AVPU1502 and AVPU1504 produced significantly (P=0.05) greater fruit weight per plant (2.02 and 2.71 kg/plant) compared with the commercial check (1.31 kg/plant). In the location 2 , AVPU1504 and AVPU1505 yielded better (10.66 and 11.41 kg/plant) compared with the commercial check (2.3 kg/plant). Beta-carotene content of AVPU1504 and AVPU1505 in location 1 were highest (6017 and 4759 μg/100 g fresh weight, respectively) compared with the commercial check (1213 μg/100 g fresh weight). Similarly in location 2, beta-carotene content of AVPU1504 and AVPU1505 were nearly four times higher (5692 and 4283 μg/100 g fresh weight) than recorded in the commercial check (1807 μg/100 g fresh weight). In location 1, total sugars of lines ranged from 12.7 to 15.9 °Brix, while in location 2, it ranged from 11.7 t0 15.6 °Brix) and it was comparable to the sugar content of the commercial check (14.3 and 14.0 °Brix, in locations 1 and 2, respectively). The pumpkin trial failed in Location 3. In conclusion, pumpkin lines developed by World Vegetable Center recorded better yield and beta-carotene content in trials in highland areas of Thailand compared with the current commercial cultivar grown by local farmers.

Agronomic Performance of Some New Kirkagac Melon (Cucumis melo L. var. inodorus) Hybrids Developed by DH Technique

Nebahat Sari, Irem Bicer, Ilknur Solmaz, Mihriban Namli
Cukurova Univ, Adana, 01330, Turkey

Kirkagac melons are the primary melon groups grown widely and economically in Turkey. These melons are odourless winter melons belong to Cucumis melo var. inodorus. Their fruits are thick rinded, dark dotted and spotted on yellow rind. In this study irradiated pollen technique was used to obtain 100 % homozygous pure lines in 18 months. A total of 49 experimental hybrids were developed  by the cross breeding programme of distant relatives in pure lines.

The plant growth, total yield and some fruit characteristics performances of hybrids were examined in open field conditions for two years. As a result; some of the hybrids were found promissing in terms of investigated parameters and will be registered to be used as new Kırkagaç hybrid cultivars.

Sucrose Concentration and Watermelon Flavor Quality

Cathy Pham-Nguyen¹, Katriona Vigueras², Ebenezer Ogundiwin¹, Yen Ming Chang², Elly Soeryapranata¹
¹BASF Vegetable Seeds, West Sacramento, CA, USA. ²BASF Vegetable Seeds, Acampo, CA, USA

Watermelon flavor is mainly associated with sweetness. Brix is used as indicator for watermelon flavor quality. Our previous studies indicated selecting flavor quality using Brix alone will not result in varieties with high flavor acceptance. Ripe watermelons have varying levels of glucose, fructose, and sucrose. Fructose is considered the most important saccharide for watermelon flavor because of its sweetness intensity. Our previous studies indicated small variation in fructose concentrations among watermelon hybrids and breeding lines. Therefore, variation in watermelon sweetness intensity is unlikely attributed to fructose. Conversely, the role of sucrose on the watermelon flavor quality is rarely revealed. The current study was  aimed at exploring sucrose contribution to watermelon flavor quality. Understanding the role  of sugar components on watermelon flavor acceptance will assist breeding program to setup screening criteria for flavor quality. Seventeen F1-crosses were made using selected parental lines (Pn). High sucrose line (A) was one of the parents in nine F1-crosses (Pn×A). Low sucrose line (B) was one of the parents in eight F1-crosses (Pn×B). Sensory and sugar analysis were performed on parental lines and F1 populations. Fructose concentrations of parent A and all F1- crosses were 3.5%-4.0%. Fructose concentration of parent B was 2.2%. Sucrose concentrations of parents A and B were 6.0% and 0.7%, respectively. Sweetness intensities and flavor acceptance of A were significantly different from B. Sucrose concentrations of Pn×A were 4.7%- 6.2%. Sweetness intensities and flavor acceptance scores of Pn×A were similar to A. Likewise, sweetness intensity and flavor acceptance scores of the highest sucrose genotype among Pn×A were similar to the lowest sucrose genotype . Conversely, Pn×B had sucrose concentrations 2.2%-4.3%. Sweetness intensities and flavor acceptance scores of Pn×B were significantly different from parent B. Moreover, sweetness intensity and flavor acceptance scores of the highest sucrose line among Pn×B were higher than the lowest sucrose line. Sensory and sugar data indicate the importance of sucrose in determining watermelon flavor quality. Sucrose level of 4.5%-5.0% seems to be optimal for good flavor quality. Increasing sucrose level >5.0% does not seem to improve flavor quality of watermelons.

Variety Trials

Marlee Trandel¹, Penelope Perkins-Veazie¹, Jonathan Schultheis²
¹North Carolina State University, Kannapolis, USA. ²North Carolina State University, Raleigh, USA

Hollow heart (HH), a serious internal defect most commonly found in triploid (seedless) watermelon, causes a crack in the center of the fruit. Watermelon cultivars with lower tissue firmness are thought to be more prone to HH. Using data from three triploid watermelon cultivar studies conducted from 2012-2014 at the Central Crops Research Station, Clayton, NC correlations were made between tissue firmness and HH incidence within 5 different HH categories. Transplants were planted in May; plot size was one row, 10 plants/plot at 1 m in- row-spacing. Plots were 7.5 m long with 3 m alleys. Pollinizers ‘Ace’ and/or ‘SP-6’ were planted within plots after plants 1, 4, 7 and 10. Trickle irrigation was utilized and fertigation was applied weekly. Fruit were harvested and rated (0-4, none-severe) for HH after cutting fruit from the stem to blossom end. Flesh firmness was taken using a Penetrometer FT 011 with a 7/16” plunger tip, (QA Supplies LLC, Norfolk, VA). Pressure was taken in five areas of the fruit; stem end, top side, ground spot side, blossom end, and center. Averaging across all cultivars and reps, a negative correlation (<0.32) was indicated between tissue firmness and incidence of moderate to severe HH (2-4) in 2012 and 2013. A positive correlation (>0.15) was found between increased tissue firmness and fruit with little or no HH (0-1) and a negative correlation (<0.15) between tissue firmness and fruit with moderate to severe HH (2-4) in the 2014 study. Tissue firmness correlations were highest in all three studies with pressure readings taken at the center of the fruit. The correlations suggest that cultivars with lower tissue firmness may      have higher incidences of HH. In all three studies, cultivars that appear to be linked to HH include Bold Ruler, Liberty and Affirmed, having the highest percent of HH. With further analysis, we plan to determine if tissue firmness and cultivar interact, and which factor most contributes to the incidence and severity of HH. Partial Funding provided by the Specialty Crop Block Grant Program at the U.S. Department of Agriculture (USDA) through Grant 14-SCBGP-CA- 0006 (The CucCAP Project)

Research Aspects of Cucurbits in India

Vidya Wati
B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India

Cucurbits are vegetable crops belonging to family Cucurbitaceae, which is mainly comprised of species that are consumed worldwide. The family consists of about 118 genera and 825 species. There is tremendous genetic diversity within the family, and the range of adaptation includes tropical, temperate and subtropical regions, arid deserts. The genetic diversity in cucurbits extends to both vegetative and reproductive characteristics and considerable range in the monoploid (x) chromosome number including 7 Cucumis sativus, 11 Citrullus spp., Momordica spp., Lagenaria spp., Sechium spp., and Trichosanthes spp., 12 Benincasa hispida, Coccinia cordifolia, Cucumis spp. other than C. sativus, and Praecitrullus fistulosus, 13 Luffa spp., and 20 (Cucurbita spp.). Cucurbits are consumed in various forms, i.e., salad (cucumber, gherkins, long melon), sweet (ash gourd, pointed gourd), pickled (gherkins), desert (melons), culinary  purposes (bitter gourd), and are well known for their unique medicinal properties. Plant genetic resources management, varietal development, hybrid development, breeding for resistance, clonal selection and off-season vegetable production are some areas that require special concern. Cucurbits are affected by a number of diseases and pests that are of national importance and cause of important economic losses in cucurbits. Breeding objectives of cucurbits can broadly defined by five categories, viz. earliness, sex ratio, growth habit and sensitivity to photoperiod, fruit yield, and fruit quality. The main goal of research on Cucurbitaceae in India is to improve productivity on sustainable basis. Cucurbits, comparatively, have small genomes, which is very useful for gene identification and marker development. Productivity is a major criteria to get maximum return, but like other vegetable crops, quality and availability of the product during lean periods are also equally important to fetch better price in the markets. There is a need to introduce diverse germplasm of cucurbits with an emphasis on biotic and abiotic stresses, desirable yield and quality characters. The mapping of gynoecious and parthenocarpic genes needs much more attention, as it may be commercialized for economic seed production and off-season protected cultivation. Cucurbit germplasm including wild relatives assembled at NBPGR and other centers across the country should be characterized and evaluated in different agro-climatic zones.