Effects of different combinations of N, P and K at different time interval on vegetative, reproductive, yield and quality traits of mango (Mangifera Indica. L) cv. Dusehri / Efeitos de diferentes combinações de N, P e K em diferentes intervalos nas características vegetativas, reprodutivas, produtivas e de qualidade da manga (Mangifera indica. L) cv. Dusehri

The experiment was carried out on mango cv. Dusehri to investigate the effect of N, P and K fertilizers on vegetative, reproductive growth, yield and fruit quality. Eight different fertilizer combinations such as T1 (control), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) and T8 (NPK) were used. Individual or combine fertilizer application of N (1000 g), P (750 g) and K (750 g) were applied during growing season in February and August. All the treatments significantly influenced on vegetative growth, flowering, fruiting, yield and other physiochemical attributes of mango as compared to control. Least effect was observed with individual fertilizer application while combine fertilizer treatments enhanced most of the investigated parameters. Especially, qualitative traits showed non significant differences between treated and untreated mango trees. However, among the different treatments T8 (NPK) showed significance for fruiting aspects such as maximum size of growth flushes (177.51 mm), total number of panicles/tree (845), total number of flowers/panicle (974), sex ratio (69.18%), fruit retention (13.85%), total number of fruits/tree (379), yield (82 kg/tree), fruit weight (197.5 g), pulp weight (135.5 g) and physiochemical parameters namely TSS (24.53), Vit. C (57.63 mg/100 mL) and total sugar (20.84%). In general, combine application of NPK (T8) were the most effective in enhancing fruiting aspects, yield, physiochemical characteristics as well as improved fruit quality of mango trees.

O experimento foi realizado em manga cv. Dusehri para investigar o efeito dos fertilizantes N, P e K no crescimento vegetativo, reprodutivo, produtividade e de qualidade do fruto. Foram utilizadas oito combinações diferentes de fertilizantes: T1 (controle), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) e T8 (NPK). Cada tratamento de N(1.000 g), P (750 g) e K (750 g) foi aplicado duas vezes durante a estação de crescimento em fevereiro e agosto. Todos os tratamentos influenciaram significativamente o crescimento vegetativo, floração, frutificação, produtividade e outros atributos físico-químicos da manga em relação ao controle. Menos efeito foi observado com a aplicação individual de fertilizante, enquanto os tratamentos combinados aumentaram a maioria dos parâmetros investigados. Especialmente as características qualitativas mostraram diferenças não significativas entre mangueiras tratadas e não tratadas. No entanto, entre os diferentes tratamentos, T8 (NPK) apresentou significância para aspectos de frutificação, como tamanho máximo de folgas de crescimento (177,51 mm), número total de panículas/árvore (845), número total de flores/panícula (974), razão sexual (69,18%), retenção de frutos (13,85%), número total de frutos/árvore (379), produção (82 kg/árvore), peso do fruto (197,5 g) e peso da polpa (135,5 g), além de parâmetros físico-químicos, como TSS (24,53), vitamina C (57,63 mg/100 mL) e açúcar total (20,84%). Em geral, a aplicação combinada de NPK (T8) foi a mais eficaz no aprimoramento dos aspectos de frutificação, produtividade, características físico-químicas, além da melhoria da qualidade dos frutos das mangueiras.

In vitro control of fasciation in proliferating nucellar embryos of Mangifera indica L. var totapari red small for cloning.

Nucellar tissue contained in ovular halves of young fruits of Mangifera indica L. totapari red small, a dwarfing rootstock, differentiated fasciated embryonal structures in presence of 6-benzylaminopurine [BAP(0.15 mg l(-1))], 6-(gamma-gamma-dimethylallylamino) purine [2iP(0.15 mg l(-1))] and indole-3-acetic acid [(IAA(0.5 mg l(-1))] incorporated in the semisolid medium during 50-60 days. Due to embryonal fasciation, hardly 2-3 well-formed embryos could be obtained per culture of proliferating embryos. Of the 3 ethylene inhibitors [L-alpha-(2-aminoethoxyvinyl)-glycine-HCl (AVG), AgNO3 and salicylic acid (SA)] used, embryonal fasciation and necrosis of intervening tissue was completely controlled by 3-4 subcultures of fasciated mass of embryos under the influence of AVG (0.05 mg l(-1)) in presence of adenine sulphate [AdS (50 mg l(-1))] incorporated in the same medium. Almost synchronized development of isolated embryos, measuring ca 2 cm in length, was observed in a different medium used in liquid stationary state and supplemented, particularly with stress-producing substances [abscisic acid (ABA, 0.01 mg l(-1)); and polyethylene glycol (PEG, 100 mg l(-1))] besides certain other modifications. About 34% convertibility of processed embryos was obtained during a period of 90 days. The plantlets had well-developed roots along with laterals which were longer than leafy shoots. In vitro raised plants survived ex vitro for about 2 months.