The growth, yield, and vitamin C content of the radish (Raphanus sativus L.) can be influenced by the Tithonia diversifolia and Parkia biglobosa, when used as green manure. The study, published in the journal Agroforestry Systems, compared the efficacy of the two materials with NPK (nitrogen, phosphorous, and potash (potassium)) fertilizers that are heavily used in the industry.

• While there is little information regarding the potential of P. biglobosa to provide nutrients to plants, T. diversifolia had been previously noted to supply crop nutrients despite the complex nutrient required in the leaves.
• The authors also noted that both P. biglobosa and T. diversifolia can provide an ample amount of biomass to sustain crops and help them grow.
• For the study, three main factors were considered: the effect of the green biomass on the growth of the radish, its ability to influence the yield, and its overall vitamin C content.
• Researchers found that a contribution of 10 tonnes per hectare of T. diversifolia can compete with that of NPK. On the other hand, the effect of P. biglobosa was not able to be fully expressed because of its slow mineralization.
• Moreover, a combination of the two materials at varying levels also contributed to the growth and yield of the radishes; however, these were not significant enough.

Researchers concluded that using T. diversifolia as organic manure at 10 tonnes per hectare can produce similar yields as that of 200 kilograms per hectare of NPK fertilizer. Moreover, T. diversifolia is eco-friendly and readily available over NPK, which has both economic and environmental impacts.

Journal Reference:

Aboyeji CM, Adekiya AO, Dunsin O, Agbaje GO, Olugbemi O, Okoh HO, Olofintoye TAJ. GROWTH, YIELD AND VITAMIN C CONTENT OF RADISH (RAPHANUS SATIVUS L.) AS AFFECTED BY GREEN BIOMASS OF PARKIA BIGLOBOSA AND TITHONIA DIVERSIFOLIA. Agroforestry Systems. 2017 Dec 8:1–10. DOI: 10.1007/s10457-017-0174-6