Shoot-to-root ratios and root biomass of cool-season feed crops in a boreal Podzolic soil in Newfoundland

Abstract

. 2005. Shoot-to-root ratios and root biomass of cool-season feed crops in a boreal Podzolic soil in Newfoundland. Can. J. Soil Sci. 85: 369-376. Barley (Hordeum vulgare L.) and oat (Avena sativa L.) crops are grown as feed grains by Newfoundland (NL) dairy farmers. The cereals are either grown as monoculture or intercropped with field pea (Pisum sativum L.) with or without N fertilization. Two experiments were conducted in both 2000 and 2001 to evaluate the shoot-to-root (S:R) weight ratios and root biomass in these production systems. Experiment 1 involved monocultures of pea sown at 150 kg ha -1 , and barley and oat each sown at 170 kg ha -1 . For pea-barley and pea-oat intercrops, pea was sown at 150 kg ha -1 and each cereal component was sown at either 85 and 170 kg ha -1 . The seven treatments were referred to, respectively, as pea 150 150 -oat 170 , indicating that the cereal component of the intercrops contributed more to the root biomass than the pea at the higher seeding rate of the cereal crop. In exp. 2, the 0 kg N ha -1 rate produced the lowest S:R ratios irrespective of the barley seeding rate. When N was applied, both the shoot biomass and root biomass appeared to be increased at the high barley seeding rate. The feed grain production practice in Newfoundland could affect root biomass production in soil. High cereal seeding rates in either monoculture and intercrop systems are required to maximize root biomass production and therefore increase C inputs into the soil . . La culture intercalaire du pois avec les céréales augmente la biomasse des racines de la combinaison pois 150 -orge 85 de 31 % et celle de la combinaison pois 150 -avoine 85 de 48 %, comparativement à celle du pois 150 . Elle s'accroît cependant de 109 % pour la combinaison pois 150 -orge 170 et de 104 % pour pois 150 -avoine 170 , signe que la céréale contribue plus à la production de racines que le pois à la densité de semis plus élevée de la céréale. Dans la deuxième expérience, le taux d'application de 0 kg de N par hectare a donné le plus faible ratio S:R, peu importe la densité de semis de l'orge. L'amendement N semble augmenter la biomasse des pousses et des racines à la plus haute densité de semis de l'orge. La culture de céréales fourragères à Terre-Neuve pourrait modifier la biomasse des racines dans le sol. Une densité de semis élevée pour les céréales cultivées seules ou avec une autre culture maximiserait la production de la biomasse des racines, donc l'apport de C dans le sol.

Cosmic Ray Neutron Soil Moisture Estimation Using Physically Based Site‐Specific Conversion Functions

“…The approximately 1‐m‐high crop is assumed to be composed of 85% water and 15% cellulose. The root zone is shallow (60–90 cm) (Refsgaard et al, 2011), and the wet below‐ground biomass is estimated to 0.76 t/ha using the root‐to‐shoot ratio (the weight of the roots to the weight of the aerial part of the plant) for barley of 0.09 (Kwabiah et al, 2005). In the period between harvest in late summer and sowing in spring, crop residue is left on the fields (e.g., stalks and stubbles).…”

Effect of Alfalfa Grown for Forage on Soil Fertility Related to Mineral and Organic Fertilization

“…With maximizing formation of root biomass C inputs into the soil increased. Root biomass contains approximately 40% С and about 18% of the root С for year could be converted in humus (Kwabiah et al, 2005). Tiwari et al (2002) have also reported that the inclusion of manure in the fertilization schedule improved the organic carbon status and available N, P, K and S in soil, thus sustaining soil health.…”

Morphological Parameters and Rations in some Mixtures with Subclover

“…Root mass development in legumes is important having in a mind that 60% of fixed nitrogen is concentrated in the roots 39 . With maximizing formation of root biomass C inputs into the soil increased 40 . Legumes in mixture with proper grasses are stimulated for the assimilation of more fixed nitrogen due to the effect of grass component on the balance of the mineral substances 14,41 .…”