Forage Potential of Cereal/Legume Intercrops: Agronomic Performances, Yield, Quality Forage and LER in Two Harvesting Times in a Mediterranean Environment

Monica Bacchi,Antonio Pellicanò,Antonio Calvi,Giovanni Preiti,Michele Monti,Emilio Lo Presti

doi:10.3390/agronomy11010121

Abstract

The crop yield and quality of seven annual forages (four grasses and three legumes) in sole crop and in mixtures (ratio 50:50) for oat (Avena sativa L.), Italian ryegrass (Lolium multiflorum Lam.), triticale (x Triticosecale Wittmack), barley (Hordeum vulgare L.), pea (Pisum sativum L.), berseem (Trifolium alexandrinum L.) and common vetch (Vicia sativa L.) were evaluated in a two-year field experiment adopting two harvesting times, green fodder and silage. The main bio-agronomic traits, dry matter forage yield (DMY) and quantity of crude protein (CP) were determined in both sole crop and intercrop. The land equivalent ratio (LER) was used for evaluating biological efficiency and competitive ability of the intercrops. Our results showed that the total calculated LER for fodder and protein yields was always greater than one and corresponded to crop yield advantages of 16.0% and 11.5%, respectively. Our data also highlighted the low competitive ability of the ryegrass in intercrop, which achieved the lowest yield among all the mixtures. Conversely, the same grass showed the best green fodder quality, due to the high incidence of the legume, equal (on average) to 46%. Triticale and barley, harvested for silage (hard dough stage), provided the best quantitative and qualitative results both in sole crop and intercropped with common vetch and pea, determined mainly by the cereal grain.

Highlights

Most of the arable lands in southern Italy are subjected to a typical Mediterranean climate characterized by cold and wet winters and hot and dry summers, with increasingly scarce and irregular rainfall throughout the year
The oat/common vetch mixture has been previously reported as producing a higher protein content than the other combinations with legumes [39], but our results showed a higher protein content in the oat/pea intercrop
The total foragefiyrsitelcduto, fthaelliinntetercrrcorpospws iwtharsyseigmraislasrshtoowtheadt tohfeglorawsessetsparnoddumctiuocnh, bhuigt halesro the bestthan legumes in purqeuacluityltfuorreagaetdbuoetho thearhvigehstprteimsenecse. oTfhleeguremaes,ownhsicfhowr atsh4e6%hiognhaevreyraiegled. Fiunrthermore, such systems is that rtyheegirnatsesricnrmopixptuedreswpiethcicelsovdeor nafotetrctohme fiprestteufsoersthhoewseadmaehnigihchreegarroewatshacnadpacity, prothereby tend to utilizveidtihnge ainvJauinlaebalevreerysoleuarfcyeasnidn paaclaotmabplelefmoraegnetathryatwcoauyl.d be used for green fodder or first Tcuhte,rtehfoerien,tienrtcerropgcprrraooszdpiwunacgied.trhTosh;prteythiseeoegcnsoaramanlsdelsoccuwsethr,eeoudawslseu,efusmdltafotoihnrimlesyillpiaongrwoeco,vesmsehtbofoiwpnrreaaodtgidoteruniytcwiitceiaiotllhdenav,anebndtucdhbtaqaarunllesdayolpittoetyhab.,eeAsehbtxoectwshetleel-edntthfeorbaegset quality forage due to the high presence of legume, which was 46% on average

Summary

Introduction

Most of the arable lands in southern Italy are subjected to a typical Mediterranean climate characterized by cold and wet winters and hot and dry summers, with increasingly scarce and irregular rainfall throughout the year. The Mediterranean and Eastern Europe increasingly experience drought in summers, so the forage yield during spring-summer seasons can be severely affected by adverse and changing climatic conditions [1] This trend is causing green forage, hay and silage crops to be conceivable only during the autumn-spring seasons, creating the need to intensify these productions during the wet season by extending the harvest season, when irrigation is generally not available. In these environments, the interest in intercropping—-mixing mainly cereals and legumes— -is increasing in order to reach farm self-sufficiency for fodder production in low-input cropping systems [2]. A renewed interest in these systems has already been observed in developed countries due to the increasing awareness of biodegradation produced from the heavy use of nonrenewable resources [4] and in order to develop sustainable farming systems for forage or grain production [5,6]

Methods

Results

Conclusion