Evaluation by grafting technique of changes in the contribution of root-to-shoot development and biomass production in soybean (Glycine max) cultivars released from 1929 to 2006 in China

Abstract

Root traits are essential for optimising nutrient and water absorption and anchorage. However, changes in root traits and the contribution of root-to-shoot growth and development of soybean (Glycine max (L.) Merr.) across a century of breeding are poorly documented. In this study, we adopted a grafting technique, using 55 cultivars released in the three main soybean-production regions in China as rootstocks in a pot experiment and 24 cultivars from the Yellow-Huai-Hai Valley (YHH) region as rootstocks in a field experiment, with cv. Zigongdongdou as the common scion. Changes in soybean roots, including dry weight (DW) of roots, lateral root number (LRN) and taproot length (TRL), and their contribution to shoot development and biomass formation, including shoot DW, plant height and node number, were evaluated under optimal conditions in 2011. Aboveground traits declined with year of release in the YHH region and did not vary over time in the northern Heilongjiang province and mid-south Heilongjiang region except for shoot DW. The root traits root DW, LRN and TRL were similar over years of release in the pot and field experiments. The results suggest that the newer cultivars have lesser shoot growth and root capacity but the same amount of root growth as older cultivars. Root traits did not change during selection, suggesting that improvement in soybean root traits should be an aim in future breeding.

A nitrogen fixing symbiosis-specific pathway required for legume flowering

“…The grafting method was modified according to a previous description ( 58 ). Briefly, soybean seedlings at 7 days after sowing were selected to cut the scion with a blade, which was trimmed into a wedge-shaped end.…”

Soil Moisture, Nutrients, Root Distribution, and Crop Combination Benefits at Different Water and Fertilizer Levels during the Crop Replacement Period in an Apple Intercropping System

“…Furthermore, it is possible that within the interval of positive water-fertilizer beneficial effects on Yd, water-fertilizer use efficiency under drip irrigation was higher than that under flood irrigation, resulting in the considerable differences observed in Yd between drip and flood irrigation treatments. A possible explanation for the significant increase in ET after crop replacement (Table 2) is that maize has a fibrous root system and soybean has a taproot system [6,7]. The high soybean RLD allowed soybean to absorb and use water from deeper soil layers more efficiently.…”

“…Root system types directly determine the capacity of a crop to absorb soil water and nutrients [3], and the spatial distribution characteristics of root systems in the soil affect crop water and fertilizer regulation [4]. Maize has a shallow, fibrous root system [5,6], whereas soybean has a deep taproot system [7]. Consequently, intercropping systems are susceptible to uneven distribution of water and nutrients due to variations in root distributions of intercrops after changing crops.…”

Differential light-dependent regulation of soybean nodulation by papilionoid-specific HY5 homologs

“…The grafting method for the soybeans was modified according to a previous description. 57 Briefly, at 3 days after sowing, the scions ll Current Biology 32, 1-13.e1-e5, February 28, 2022 e4…”