Development of a new winter squash cultivar ‘Houchouko 1’ with short internodes and stable fruit position

Currently, most of the winter squash cultivated in Japan has long primary stems and the position of fruit-bearing nodes is inconsistent.
As a result, it takes time to find fruits and harvesting is labor intensive.
One way to reduce this labor is to breed cultivars with uniform fruit positions.
Therefore, we developed a new cultivar, ‘Houchouko 1’ (winter squash, Cucurbita maxima), with a stable fruit position and short internodes.
This cultivar was bred from a cross between ‘Parent G’ (as the seed parent bred by Asahi Agria Co., Ltd.), which has a high fruiting rate, and ‘Hokkai 8’ (as the pollen parent bred by National Agriculture and Food Research Organization, NARO), which has short internodes.
The cultivars ‘Ebisu’ and ‘Houko Aokawa Kuri’ were used as controls.
The main traits of the new cultivar are as follows: 1) while the main stems of the control cultivars expanded as they matured, the stems of ‘Houchouko 1’ were short and had short internodes from early to mid-growth stages.
Hence, the distance of the fruit positions from the point of planting was typically shorter than that of the control cultivars, making it easier to find fruit to harvest; 2) the average fruit weight of ‘Houchouko 1’ was 1.3 kg, which is slightly lighter than that of ‘Ebisu’; 3) the fruit rind was blackish green with light green stripes.
The flesh was dark yellow, the same, or slightly more yellowish than that of ‘Ebisu’; 4) texture of the flesh was powdery, with a higher dry matter ratio than that in ‘Ebisu’. As ‘Houchouko 1’ has short internodes in several production area in Japan, it is expected to spread as a cultivar that can reduce the difficulty of harvesting.

IV Asian Horticultural Congress – AHC2023

K.M. Nakajima, D. Kami, K. Sugiyama, N. Murata, T. Ogura, A. Tsuji

labor-saving cultivation, F₁ cultivar, plant breeding, Cucurbita maxima, pumpkin

https://doi.org/10.17660/ActaHortic.2024.1404.90