Rhizoma peanut genotype and planting date affect biomass allocation patterns and establishment performance

Abstract

Rhizoma peanut (RP, Arachis glabrata Benth.) is an important perennial forage legume, but its adoption can be limited by relatively slow establishment. Genotype and temperature after planting of rhizomes likely affect partitioning of stored and new photoassimilates, but their impact on establishment rate is not known. To assess these relationships, planting date and RP entry effects were measured on biomass partitioning and growth responses. Treatments were all combinations of two planting dates (spring and summer) and four entries (‘Florigraze’, ‘UF Peace’, ‘UF Tito’, and the germplasm Ecoturf) replicated four times, with new plots planted in each of 2 yr. Spring‐planted Florigraze outperformed UF Peace in shoot count, shoot biomass, and root‐rhizome biomass through much of the year of planting. When planted in summer, UF Tito and UF Peace generally had earlier and greater shoot emergence, lesser root‐rhizome/shoot ratio, taller canopy height, and lesser leaf/stem ratio than Ecoturf or Florigraze. Across years, shoot biomass in the year after planting was greater for UF Peace and UF Tito than for Ecoturf and Florigraze when planted in summer (490, 387, 265, and 157 g m−2, respectively) and greater for UF Peace than Ecoturf or Florigraze planted in spring (349, 243, and 201 g m−2, respectively). UF Tito and UF Peace had greater shoot biomass in the year after planting for summer than for spring plantings, but there was no season effect for Ecoturf and Florigraze. Summer planting favored rapid establishment of upright cultivars UF Tito and UF Peace, but Ecoturf and Florigraze were less affected by season.

Growth temperature and rhizome propagule characteristics affect rhizoma peanut shoot emergence and biomass partitioning

“…Greater growth temperature produced more rapid RP shoot emergence and greater overall plant growth during early establishment, and UF Tito outperformed Ecoturf. As the greater temperature regime approximates that of summer in northern Florida, these results support recent recommendations of summer planting of RP based on field experiments (Aryal et al., 2020), especially for upright cultivars like UF Tito.…”

“…Our results suggest optimum temperature regime for shoot emergence may be around 30/20˚C under adequate soil moisture conditions. This conclusion from the growth chamber experiment was also supported by field data showing generally faster and greater shoot emergence for summer vs. spring planting (Aryal et al, 2020).…”

“…Rhizomes also serve as propagules for vegetative propagation when establishing new areas of RP. Effects of planting dates (winter/spring vs. summer) on growth and establishment success have been quantified in the field and the planting window for RP is relatively long, extending from the winter dormant period through the summer (Aryal et al., 2020; Williams, Valencia, & Sollenberger, 2002). An inherent limitation of these studies is environment conditions in the field (e.g., temperature) following different planting dates are confounded with differences in rhizome propagule characteristics associated with those dates.…”

“…Thus, the objectives of this study were to: (a) determine in a growth chamber the effect of temperature on RP growth rate and biomass partitioning during the sprout emergence period, (b) evaluate the effect of rhizome length and presence of the apical meristem on sprout emergence and biomass partitioning in a greenhouse, and (c) compare these responses for two RP entries with different growth habits. Two RP entries (decumbent germplasm Ecoturf and upright cultivar UF Tito) were chosen because in field experiments (Aryal et al., 2020) they responded differently to spring and summer planting dates, and growth temperature following planting was thought to play a role.…”

Plant growth habit and nitrogen fertilizer effects on rhizoma peanut biomass partitioning during establishment

“…Our data show that the more upright-growing UF Tito accumulated leaf area more rapidly than Ecoturf during the early establishment TA B L E 5 Year-after-planting responses of two rhizome peanut entries (Ecoturf and UF Tito) in response to N fertilizer applied in the year of planting period. As LAI is related to growth rate (Beinhart, 1963) Ecoturf and intermediate Florigraze (Aryal et al, 2020).…”