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Let $(S, d)$ be a compact metric space; let $(\Omega, \mathscr{F}, P)$ be a probability space, and for each $t \in S$ let $X_t: \Omega \rightarrow \mathbb{R}$ be a random variable, with $E(X_t) = 0$ and such that $\{X_t\}_{t\in S}$ forms a Gaussian process. In this paper we find sufficient conditions for the Gaussian process $\{X_t\}_{t\in S}$ to admit a separable and measurable model whose sample functions are continuous with probability one. The conditions involve the covariance, $E(X_s, X_t)$, of the process and also the $\varepsilon$-entropy of $S$.

The frequency of hybridisation between Brassica napus L. and Raphanus raphanistrum L. under agronomic conditions was assessed in field experiments, where R. raphanistrum were randomly planted at two different densities into large plots of B. napus. An acetolacate synthase (ALS)-inhibiting herbicide-resistant trait was used to detect potential hybrid individuals. No hybrids were detected amongst 25,000 seedlings grown from seed collected from R. raphanistrum plants. Two hybrids were obtained from more than 52-million B. napus seedlings. Both hybrids were characterised as amphidiploids (AACCRrRr, 2n = 56) and were fertile. The frequency of hybridisation into B. napus in this experiment using male-fertile B. napus was 4 × 10–8.

The mechanism of resistance to diquat and paraquat was investigated in a bipyridyl-herbicide-resistant biotype of Arctotheca calendula (L.) Levyns. No differences were observed in the interactions of these herbicides with Photo-system I, the active site, in thylakoids isolated from resistant and susceptible biotypes. Likewise, absorption of herbicide through the cuticle and gross translocation were identical in plants of the two biotypes. Foliar application of either 25 g ha−1 diquat or 200 g ha−1 paraquat rapidly inhibited CO2-dependent O2 evolution of leaf segments of the susceptible biotype. O2 evolution of leaf segments of the resistant biotype was less affected by these treatments. Fluorescence imaging was used to observe visually, as fluorescence quenching, the penetration of herbicide to the active site. These experiments demonstrated that diquat appears at the active site more slowly in the resistant biotype compared to the susceptible biotype. HCO3-dependent O2 evolution of thin leaf slices was less inhibited by diquat in the resistant biotype than in the susceptible biotype. The mechanism of resistance to the bipyridyl herbicides in this biotype of A. calendula is not a result of changes at the active site, decreased herbicide absorption or decreased translocation, but appears to be due to reduced herbicide penetration to the active site.

In Australia, glyphosate resistance has been observed in rigid ryegrass in several states including New South Wales (NSW) and South Australia (SA). Several populations of glyphosate-resistant rigid ryegrass were analyzed for the inheritance of glyphosate resistance. Eight glyphosate-resistant populations were crossed to the same susceptible population to create first filial generation (F1) families. Individuals from the F1families were subsequently treated with glyphosate. The response to glyphosate of F1families from all eight crosses was more similar to the resistant parent than the susceptible parent. Within crosses, dose responses of reciprocal F1families were not significantly different from each other, indicating glyphosate resistance is encoded on the nuclear genome in all eight populations. The level of dominance observed in dose–response experiments ranged from partial to total within the herbicide doses tested. F1individuals from five of the populations were crossed with susceptible (S) individuals to create backcross (BC) populations. Most of the families from these BC populations segregated in a manner consistent with a single gene controlling glyphosate resistance. These results indicate that resistance is inherited as a single dominant allele in four out of the five glyphosate-resistant rigid ryegrass populations. Such information is vital in the development of management strategies for glyphosate resistance in Australia.