Context. Data are lacking on the effects of heading date of perennial ryegrass (Lolium perenne L.) on ryegrass persistence.

Aim. We aimed to determine the impact of heading date on perennial ryegrass persistence.

Method. Two mid-heading (Samson, Bronsyn) and two late-heading (One50, Rohan) cultivars, infected with Epichloë endophytes (AR37, nea2/6 or standard toxic), were established in a replicated plot study grazed by cattle in a subtropical environment of the upper North Island of New Zealand. Persistence characteristics were quantified at least five times per annum, over 4 years.

Key results. Late-heading cultivars had higher yield, nutritive value, perennial ryegrass content in pasture dry matter, ground cover and tiller density than mid-heading cultivars. There were large seasonal impacts on all ryegrass characteristics, with a major decline over summer and recovery during late autumn into early spring, with less recovery in the final year. Overall, there was a strong linear decline in ryegrass content measured during spring (2018–21).

Conclusions. The two late-heading cultivars were more persistent than the two mid-heading cultivars, although persistence declined over 4 years for all cultivars.

Implications. Results support industry recommendations of choosing late-heading cultivars for improved pasture quality and persistence.

Context. Tillering is generally considered counterproductive for grain yield in maize (Zea mays). However, recent research defies that idea and suggests that the effects of tillering on grain yield depend on the yield-environment.

Aims. To synthesise the impact of tillering on maize grain yield across a wide range of environments.

Methods. Literature regarding tillering in maize was assessed to create a multi-environment database of grain yield per unit area and per plant of side-by-side comparisons of grain yield of tillered versus de-tillered treatments. Regression analyses and mean comparisons were used to compare the performance of tillered and de-tillered crops.

Key results. The maximum plant density in the database was 7 plants m⁻². Tillered crops out-yielded de-tillered crops irrespective of the de-tillered grain yield (y-intercept = 841 kg ha⁻¹, P < 0.01 and slope = 1, P = 0.91). For the lower tercile of yield-environments (i.e. lower than 5269 kg ha⁻¹), the frequency of lower yields on tillered crops was higher (all database = 0.21, Pampas = 0.5) than in the mid or high terciles (all database < 0.13, Pampas < 0.18). Across environments, individual plant yield was higher for tillered crops (42 g plant⁻¹ or 16% difference), but that difference decreased as the de-tillered individual plant yield decreased turning into zero below 136 g plant⁻¹.

Conclusions. Within the limitations of the data set, tillering was generally beneficial or indifferent for grain yield, but detrimental effects may be recorded in very low yield-environments.

Implications. Tillering does not condition maize yield across most environments.

Context. Data are lacking on the effects of selected endophytes of perennial ryegrass (Lolium perenne L.) on ryegrass persistence.

Aim. We aimed to determine the impact of Epichloë endophyte on the persistence of mid- and late-heading perennial ryegrass cultivars.

Method. Two mid-heading (Samson, Bronsyn) and two late-heading (One50, Rohan) cultivars, infected with selected endophytes (AR37, nea2/6) or with standard toxic endophyte, were established in a replicated plot study grazed by cattle in a subtropical environment of the upper North Island of New Zealand. Persistence characteristics were quantified at least five times per annum, over 4 years.

Key results. Endophyte strain had an effect on persistence; infection with standard endophyte resulted in higher ryegrass ground cover percentage, ryegrass content in pasture dry matter and autumn yield than infection with nea2/6 on many occasions, and with AR37 on some occasions. There were negligible impacts on ryegrass tiller density or nutritive value. Trends were dominated by the main effect of endophyte; interactions with heading date were inconsistent.

Conclusions. Cultivars were more persistent when infected with standard endophyte than with selected endophytes, although persistence declined over 4 years for all cultivars and irrespective of heading date.

Implications. Reliance on selected endophyte is unlikely to prevent persistence decline of perennial ryegrass in a subtropical environment. Other strategies will be required to maintain the persistence of high-quality pastures based on perennial ryegrass.