Improvised canopy architecture enhanced high yield through better light interception in guava under sub-tropics

Guava (Psidium guajava L.) is a climate-resilient fruit known for its prolific yield. Effective canopy management is essential for achieving high quality and productivity; however, the traditional open central leader system can lead to excessive canopy growth and a sharp decline in yield. To address this, ICAR-CISH has developed an improvised Espalier canopy system that trains guava on 5–6 tiers, allowing for improved light exposure throughout the foliage. Research was conducted on the CISH-Lalit, CISH-Shweta, and CISH-Lalima varieties trained under both Espalier and Open Central Leader systems to evaluate various physiological and agronomical parameters. The study revealed that tree architecture significantly influenced growth, yield, and physiological traits. Notably, CISH-Lalima and CISH-Lalit varieties intercepted the most light across all canopy layers, with ‘CISH-Lalit’ achieving the highest fruit count (78.62 fruits per tree) and yield (16.54 kg per tree) during the Mrig bahar season. More over net photosynthetic rate (Pn), Chlorophyll ‘a’ Chl ‘b’, ‘total Chl’ and water use efficiency (WUE) was higher in ‘CISH-Lalit’, while larger size fruit were observed in ‘CISH-Shweta’. Further in Espalier canopy system the fruit number tree^− 1 (61.67), fruit weight (215.74 g fruit^− 1), yield (16.88 kg tree^− 1). TSS, lycopene content (4.40 mg 100 FW^− 1), total phenolic content, chlorophyll “a”, Chlorophyll “b”, total chlorophyll and net photosynthesis were recorded maximum in guava trained on Espalier architecture. In Espalier architecture, all the canopy layers registered maximum light interception, Chl‘a’, Chl‘b’ and total Chl, yield and quality attributes. The fruits number as well as lycopene content was higher on the upper canopy layer followed by second layer from the top. Further, in open central leader system (traditional type) the most of the fruits bearing confined to upper canopy layer only. Middle and lower canopy layers experienced more light in Espalier architecture than Open central leader. Overall Espalier architecture ensured better yield realization as compared to Open central leader system due to higher Pn rate via better light interception and pigment activation and more exposed trees per unit area.