Stability analysis of garden pea ( Pisum sativum L.) genotypes under North Western Himalayas using joint regression analysis and GGE biplots

Garden pea is an important off-season vegetable in the hills of North Western Himalayas that provides high remuneration to growers. Lack of high yielding wider adaptive varieties restricts its productivity. To identify high yielding stable genotypes across environments, 48 lines were evaluated in Alpha Lattice design over seven diverse environments spreading in five locations from sub-tropical to dry temperate conditions of Himachal Pradesh during winter 2016–2017 (5 environments) and one location each during summer 2017 and winter 2017–2018. The highest mean pod yield over environments was produced by SP-3 (83.35 g) which was 20% higher over check Pb-89 while SP-6 (79.45 g) and SP-22 (76.90 g) got second and third rank with significant increase of 15 and 11% for pod yield over the check, respectively. The joint regression analysis depicted significant G × E (linear) interaction for pods/plant and pod yield/plant. Of the seven genotypes depicting stability for pod yield, SP-6 showed stability (bi = 1 and S2di = 0) for all the traits whereas SP-22 showed the same for seeds/pod and shelling percentage. G + GE biplot described Dhaulakuan as the most representative and discriminating environment for pod yield. In the mean vs. stability GGE biplot, SP-6, SP-22 and SP-17 were highly stable while SP-3 possessed medium stability. ‘Which won where’ polygon view represented SP-3, SP-6 and SP-22 as most stable for yield and pod attributes across environments, constellated into majority of the environments and can be released for commercial cultivation.