Effect of monoclonal and assorted seedling rootstocks on long term growth and yield of Hevea clones

Abstract

Seven Hevea brasiliensis clones were evaluated on two types of rootstocks, assorted seedling rootstocks (AR) and monoclonal rootstock (MR) over 19 years. Influence of rootstock on scion growth and rubber yield was assessed based on juvenile height, circumference of the main trunk (cm), number of branches, branching height and cumulative dry rubber yield (g per tree per tapping, conventionally abbreviated gt-1t-1). Highest cumulative yield (g per tree per tapping) over the 12 years for which the trees were tapped was obtained from clone RRII 105 (MR: 1076 g per tree per tapping and AR: 497 g per tree per tapping), followed by RRII 203 (MR: 661; AR: 538), RRII 208 (MR: 477; AR: 486), RRII 118 (MR: 497; AR: 452). Gl 1 yielded the least, 219 g per tree per tapping (MR) and 378 g per tree per tapping (AR); GT1 produced 335 g per tree per tapping (MR) and 375 g per tree per tapping (AR). RRII 118 had the greatest circumference at age 19 (91.4 cm on MR) 88.8 on AR, followed by RRII 105 (MR: 87.4 cm AR: 89.2 cm) and GT 1 (MR: 88.5 cm; AR: 84.4cm). Effect of scion clone was significant (p<0.01) only for trunk circumference at opening, but not for cumulative rubber yield at age 11 (4 years after opening) or cumulative rubber yield at age 19 (12 years after opening). Most importantly, rootstock and clone × rootstock interaction did not significantly affect rubber yield or tree circumference at any evaluation time. There was no evidence to suggest that growth and yield of clones was influenced significantly by rootstock type.

Seed Collection Time Effect on the Germination Rate and Growth of Rubber Tree Rootstock

“…Several studies showed that the combination of rootstocks and scion determined the incompatibility, growth, and yield [13,14]. A study by [15] suggested that the rootstock and scion interaction did not influence rubber yield significantly, implied that the assorted seeds were acceptable for rootstock seedlings. The root accumulation rate (RAR) and shoot accumulation rate (SAR) of the samples indicated that the biomass accumulation rate was not significantly different among treatments (Table 2).…”

Adubação De Porta-Enxertos De Seringueira Em Viveiro Suspenso

“…Nesse sentido, ao avaliarem sete clones de seringueira sobre porta-enxertos de mudas sortidas e portaenxertos de mudas monoclonais, Gireesh et al (2012) não observaram evidência para sugerir que o crescimento e rendimento de clones foi significativamente influenciado pelo tipo de porta-enxerto, aos 12 anos após o início da extração do látex. Contudo, Arantes et al (2010) afirmam que sementes de origem desconhecida, que possam ter sido coletadas em jardins monoclonais, podem originar p lantas com baixo vigor.…”