Influence of varying environmental conditions on biennial bearing habit of Kinnow fruit (Citrus nobilis Lour x C. deliciosa Tenora) grown at different clusters in the Punjab province, Pakistan

Influence of varying environmental conditions on biennial bearing of Kinnow mandarin was assessed at three main citrus clusters in the Punjab province, Pakistan.The selected orchards of identical features are located in districts Sargodha, Toba Tek Singh (TTS) and Vehari.The experiment was laid out in randomized complete block design by using analysis of variance technique.Fruit bearing habit was recorded first and second seasons and biennial bearing trend was observed at TTS and Vehari.Vegetative three flushes were slightly changed due to biennial bearing in warm districts TTS and Vehari.More evenness in fruit yield and quality parameters was recorded at Sargodha while significant change was observed at TTS and Vehari.Timely harvesting of orchards at Sargodha district showed regular fruit-bearing in both seasons and delayed harvesting induced biennial bearing trend more at TTS and Vehari.More physiological and ripening stage fruit drop was observed in warm conditions of Vehari and TTS while an increasing level was recorded in rainy season at Sargodha with insignificant differences in both seasons.Index terms: Citrus nobilis x C. deliciosa, alternate bearing, varying environmental conditions.Influência das variáveis ambientais na bienalidade produtiva de tangerina Kinnow (Citrus nobilis Lour x C. deliciosa Tenora) cultivada em diferentes províncias de Punjab, Paquistão RESUMO A influência de diferentes condições ambientais no manejo da alternância de produção da tangerina Kinnow foi avaliada em três principais regiões produtoras de citros na província de Punjab, Pakistão.Os pomares selecionados de características idênticas estão localizados nos distritos Sargodha, Toba Tek Singh (TTS) e Vehari.O experimento foi instalado em delineamento de blocos casualizados, utilizando a técnica de análise de variância.O hábito de frutificar foi registrado na primeira e segunda temporadas e a tendência de alternância foi observada no TTS e Vehari.