Allelochemical resistance traits of muskmelon (Cucumis melo) against the fruit fly (Bactrocera cucurbitae) in a hot arid region of India

Abstract

Host plant resistance is an important component for management of the melon fruit fly, Bactrocera cucurbitae (Coquillett), owing to difficulties associated with its chemical and biological control. Various biochemical traits including total sugar, reducing sugar, non-reducing sugar, tannins, phenols, alkaloids, flavinoid and pH contents of fruit were studied on 11varieties/ genotypes of muskmelon, Cucumis melo L., in relation to resistance against B. cucurbitae under field conditions. Significant differences were found in tested varieties/ genotypes for fruit infestation and larval density per fruit. AHMM/BR-1, RM-50 and AHMM/BR-8 were the most resistant; MHY-5, Durgapura Madhu and Pusa Sarabati were moderately resistant; AHMM/BR-13, Pusa Madhuras and Arka Jeet were susceptible; whereas Arka Rajhans and GMM-3 were the highly susceptible varieties/ genotypes to fruit fly in both seasons, 2011 and 2012. The larval density per fruit increased with an increase in percent fruit infestation and there was a significant positive correlation (r = 0.97) between percent fruit infestation and larval density per fruit. Total sugar, reducing sugar, non-reducing sugar and pH were lowest in resistant and highest in susceptible varieties/ genotypes, whereas tannins, phenols, alkaloids and flavinoid contents were highest in resistant and lowest in susceptible varieties/ genotypes. Total alkaloid and pH contents explained 97.96% of the total variation in fruit fly infestation and 92.83% of the total variation in larval density per fruit due to alkaloids and total sugar contents.

Biochemical Resistance Traits of Bitter Gourd against Fruit Fly Bactrocera cucurbitae (Coquillett) Infestation

“…Very little information is available on correlation of the biochemical traits. Biochemical characters such as total sugar and crude protein were positively correlated whereas total phenols were negatively correlated with fruit borer nfestation (Haldhar et al, 2013). Phenolic heteropolymers play a central role in plant defense against insects and pathogens (Barakat et al, 2010).…”

“…It is well established that chemical stimuli play a major role in host plant selection by insect for both feeding and oviposition (Maxwell & Jennings, 1980). Antixenosis refers to the potential plant characteristics/traits, either allelochemical or morphological, that impart or alter insect behaviour towards the host (Haldhar et al, 2013). Resistance in a given plant species, as expressed in the field, is a complex phenomenon and there is generally no single chemical to condition it.…”

Antixenotic and Allelochemical Resistance Traits of Watermelon AgainstBactrocera cucurbitaein a Hot Arid Region of India

“…The percentage fruit infestation and larval density were found to be significantly lower in resistant and higher in susceptible varieties/genotypes of watermelon. Numerous studies have shown that genotypes of the same species could differ significantly in their resistance to insect pests (Simmons & Levi 2002a,b;Thies & Levi 2003;López et al 2005;Kousik et al 2007;Simmons et al 2010;Moslem et al 2011;Haldhar et al 2013), and that this resistance was influenced by morphological and biochemical traits of plants. Our findings are in line with those of Dhillon et al (2005b) and Gogi et al (2010), who observed lower fruit infestation and larval densities on resistant than on susceptible genotypes of bitter gourd.…”

“…Total soluble solids and pH of fruit had a significant positive correlation whereas tannin, phenol, alkaloid, and flavonoid contents had a significant negative correlation with percentage fruit infestation and larval density per fruit (Gogi et al 2010). Biochemical characters such as total sugar and crude protein were positively correlated whereas total phenols were negatively correlated with fruit borer infestation (Sharma & Singh 2010;War et al 2012;Haldhar et al 2013). Similar to our findings, it has been demonstrated that phenols, tannins, and flavonoids enhanced plant defenses against insects (Gogi et al 2010;War et al 2012;Haldhar et al 2013).…”

“…Plants responsible for antibiosis resistance may cause reduced insect survival, prolonged development time, decreased size, and reduced fitness of new-generation adults (Sarfraz et al 2006(Sarfraz et al , 2007Gogi et al 2010). Antixenosis refers to the potential plant characteristics/traits, either allelochemical or morphological, that impart or alter insect behavior towards the host (Moslem et al 2011;War et al 2012;Haldhar et al 2013).…”