Effect of black beetle, in association with nitrogen and summer spelling, on pasture production on sandy soils

Abstract

Pasture production was measured on plots infested with blackbeetle,Heteron~chus ~r~tor (F.) (Scarabaeidae: Coleoptera), and mse~tIclde treated plots from 1983 to 1986 on sandy soIls near Kaitaia in Northland. Black beetle densities ranged from 11 to 27/m2 on ryegrass (Lotium perenne L.) -dominant and from 16 to 112/m 2 0n kikuyu grass (Pennisetum clandestinum Hochst.) -domin~t pastures. Livestock pulling plants from the soIl caused pasture damage on plots infested with black beetle. Insecticidal control of black beetle, however, resulted in relatively small transient increases in pasture production. In contrast, nitrogen .(N) applications significantly boosted productIo?, ranging from 35 and 25 kg dry matter ~~/kg N m spring to 25 and 17 kg DM/kg N 10 wmter for ryegrass-and kikuyu grass-dominant pastures, respectively. Spelling kikuyu grass p~sture from grazing over the summer and autumn m 198? and 1986 resulted in an increase in pasture productIOn of from 470 to 960 kg DM/ha. The role of black beetle in this grazing response was not clearly demonstrated.

A Review of Perennial Ryegrass Endophytes and Their Potential Use in the Management of African Black Beetle in Perennial Grazing Systems in Australia

“…However, there are still a number of soil-inhabiting pasture beetles whose larval forms have not yet been described (Berg et al, 2014). Pasture beetle larvae are predominantly a problem in grassland areas where they feed on humus and plant roots, decreasing plant persistence dramatically under stress conditions (e.g., grazing livestock, use of machinery, Blank and Olson, 1988; Berg et al, 2014). Some of the most cited crop and pasture pests in Australia from this family are summarized in Table 3.…”

“…Some recommendations on grazing management for pasture beetle prevention include reducing cattle numbers in the affected paddocks early in the year when damage is at its peak (Blank and Olson, 1988; Berg et al, 2014) and reducing ground cover for egg-laying in early spring by heavy grazing and/or keeping pasture short (e.g., cut for silage, Douglas, 1972). …”

Black beetle: lessons from the past and options for the future

“…The occurrence of paspalum in pastures has, at least anecdotally, declined in the last decade (a decline in paspalum abundance in Northland was noted as early as the 1970s (Percival 1977)) which has potentially removed a reservoir for beetles from which to establish new populations. This may be offset by the recent expansion of kikuyu (Pennistum clandestinum), another favourable host (Blank & Olson 1988), previously limited to Northland (Percival 1978), into the Bay of Plenty and Waikato. There are also other C 4 grasses in intensive dairy grazed pastures, present in greater abundance than paspalum (Tozer et al 2008), which can act as hosts for black beetle.…”

“…Many of these have either been taken off the market or are no longer registered for black beetle control and none are currently recommended for black beetle control in established pastures. From a number of trials in pasture (Blank & Olson 1988;King et al 1982;Watson et al 1978;Watson & Webber 1975, 1976Watson et al 1980c) and crops (Watson et al 1980b) the best beetle control seems to be achieved when insecticides are used against the early summer (december) populations of beetles. Modelling work also suggests that control directed against the early larval stages in december will have a greater impact on the damaging summer population of beetles than controls applied in early spring, before eggs are laid (east et al 1981).…”

Lime application can help protect pastures against black beetle

“…C 4 grasses, as well as ryegrasses (Lolium spp.) without a deterrent endophyte, are favourable hosts (King et al 1981a;Blank & Olson 1988;Ball & Prestidge 1992). In contrast, adult feeding, and in turn survival and oviposition are reduced by ryegrasses containing standard, AR37, NEA2 or Endo 5 endophytes (Ball et al 1997;Popay & Baltus 2001;Bell et al 2011).…”