Pioneer Hi-Bred

Given the prompt "Rome is in", can we steer a language model to flip its prediction of an incorrect token "France" to a correct token "Italy" by only multiplying a few relevant activation vectors with scalars?We argue that successfully intervening on a model is a prerequisite for interpreting its internal workings.Concretely, we establish a three-term objective: a successful intervention should flip the correct with the wrong token and vice versa (effectiveness), and leave other tokens unaffected (faithfulness), all while being sparse (minimality).Using gradient-based optimization, this objective lets us learn (and later evaluate) a specific kind of efficient and interpretable intervention: activation scaling only modifies the signed magnitude of activation vectors to strengthen, weaken, or reverse the steering directions already encoded in the model.On synthetic tasks, this intervention performs comparably with steering vectors in terms of effectiveness and faithfulness, but is much more minimal allowing us to pinpoint interpretable model components.We evaluate activation scaling from different angles, compare performance on different datasets, and make activation scalars a learnable function of the activation vectors themselves to generalize to varying-length prompts. 1

-

<p>Nitrogen (N) fertilization is an essential agronomic practice, which increases crop yields and improves soil fertility. Globally, more than 110 x 10<sup>9</sup> kg of chemical N fertilizers are applied each year with urea-N being one of the most affordable options. Upon urea hydrolysis, any portion not assimilated by crops is either volatilized as NH<sub>3</sub> or microbially nitrified (i.e., NH<sub>4</sub><sup>+</sup> oxidized) to leachable NO<sub>3</sub><sup>-</sup> and NO<sub>2</sub><sup>-</sup>. Nitrification inhibitors (NI) are increasingly co-applied as a sustainable agricultural practice and block the process of nitrification, resulting in a temporal increase of NH<sub>4</sub><sup>+</sup> in the soils. Several studies have documented the effectiveness of NIs in retaining soil NH<sub>4</sub><sup>+</sup> and increasing crop yields, but less is known about the effects of NIs on the fate of urea–N and the overall impact of NIs on the soil microbial community.</p><p>In a 60 day soil mesocosm experiment, we investigated the effects of Nitrapyrin (NI; 2-chloro-6-(trichloromethyl)pyridine) co-applied with a selection of urea-based fertilizers: urea (U); U with urease inhibitors (U+UI); methylene-urea (MU); and zeolite-coated urea (ZU), on a typical Mediterranean soil under ambient summer conditions. We showed that NI applied with urea fertilizers resulted in a slower decay of extractable NH<sub>4</sub><sup>+</sup> with a concurrent increase in NH<sub>3</sub> volatilization. Integrated measures of soil NH<sub>4</sub><sup>+</sup> were 1.5 to 3.3-fold greater when NI was applied. At the same time, there was a 10 to 60% reduction in integrated measures of NO<sub>3</sub><sup>-</sup> and NO<sub>2</sub><sup>-</sup> when NI was applied with the tested fertilizer types, except MU fertilizer where the integrated measures of NO<sub>3</sub><sup>-</sup> and NO<sub>2</sub><sup>-</sup> doubled. Upon urea hydrolysis, the released NH<sub>4</sub><sup>+</sup> was transformed to NO<sub>3</sub><sup>-</sup> and NO<sub>2</sub><sup>-</sup>, which subsequently decreased in concentration following a typical nitrification - denitrification pathway in the absence of plants. Soil N<sub>2</sub>O emissions from urea fertilizers were reduced by 40% with UI, 50% with NI, and 66% with NI + UI.</p><p>Interestingly, 15 days after the application of NI, there was a decrease in bacterial abundance (eub genes; qPCR) in all fertilized treatments. NI dramatically reduced the abundance of ammonia-oxidizing microbes (amoA genes) and there were fewer bacteria associated with denitrification genes (nirK, nirS, nosZ) when NI was applied. </p><p>At the end of the experiment, there was no significant difference in total N among all fertilized soils. Total N was in excess when compared to the control, and it was a considerable N pool potentially immobilized in microbial biomass in the absence of crops.</p><p>In conclusion, the use of NI doubled NH<sub>4</sub><sup>+</sup> retention in the soil and decreased soil N<sub>2</sub>O emission by 50%, through negatively affecting ammonia oxidizing and denitrifying microbes and subsequently reducing soil available NO<sub>3</sub><sup>-</sup> and NO<sub>2</sub><sup>-</sup>. The application of NIs should be carefully planned and synchronized (timing) with crop growth to reduce subsequent N transformations and N loss to the environment.</p><p><strong>Keywords</strong><strong>:</strong> urea, zeolite, methylene-urea, nitrification inhibitor, nitrapyrin, calcareous soil, soil nitrogen</p>

Sunflower broomrape (Orobanche cumana Wallr.) is a holoparasitic plant species with a 12 restricted range of hosts both in the wild, where it mainly parasitizes Artemisia spp., as 13 well as in agricultural fields, where it only grows on sunflower (Fernández-Martínez et 14 al., 2015).It is not present in the wild in Iberian Peninsula, but exclusively found in race G populations from the Black Sea area (Martin-Sanz et al. 2016).Following 48 recently proposed nomenclature (Martin-Sanz et al. 2016), this population is proposed 49 as race G ALE .This is the first report of O. cumana on sunflower in Portugal.Prospective 50 surveys are required to identify the areas affected by broomrape in that country and 51 start urgently an integrated control program to avoid its expansion to other sunflower 52 areas in Portugal and Spain.

Meristem fate is regulated by trehalose 6-phosphate phosphatases (TPPs), but their mechanism of action remains mysterious. Loss of the maize TPPs RAMOSA3 and TPP4 leads to reduced meristem determinacy and more inflorescence branching. However, analysis of an allelic series revealed no correlation between enzymatic activity and branching, and a catalytically inactive version of RA3 complements the ra3 mutant. Together with their nuclear localization, these findings suggest a moonlighting function for TPPs.

Western corn rootworm (Diabrotica virgifera virgifera LeConte) presents significant pest management challenges for farmers in both North America and Europe. IPD072Aa, a protein derived from Pseudomonas chlororaphis, has previously been shown to have activity against western corn rootworm. In the current study, the spectrum of activity of IPD072Aa was evaluated in controlled laboratory diet bioassays. IPD072Aa was fed at high concentrations in subchronic or chronic bioassays to 11 different insect species, representing 4 families within Coleoptera, and an additional 4 species representing four families of Lepidoptera. No adverse effects were noted in the Lepidoptera species. Within the order Coleoptera, western corn rootworm was the most sensitive species tested. A range of responses was observed within each of the four families of Coleoptera evaluated that included either no-observed effects or reduced growth, developmental delays, and/or reduced survival. These data will help inform the environmental risk assessment of genetically modified plants that express the IPD072Aa protein for western corn rootworm control.

In maize breeding programs conducted by private companies, it is common to perform the product advanced trials (PAT) in several cultivation environments in order to better recommend the new hybrids, as well as to provide opportunities for the farmers to evaluate their products. The aim of this study was to describe the adaptability and stability of maize hybrids from unreplicated PATs using a multivariate approach combined with univariate methods. We considered the grain yield data of twelve maize hybrids evaluated in a PATs network conducted by the company DuPont Pioneer in 80 cultivation environments in the states of Minas Gerais and Goias, in second-crop of 2014. The AMMI analysis was employed and additionally we applied the methods based on bisegmented linear regression, Lin and Binns index (1988) and Annicchiarico index (1992). Significant differences were verified among the tested hybrids. The macro-environmental variation and the effect of hybrid by environment (H x E) interaction were expressive. The application of the AMMI method allowed the study of the H x E interaction based on maize PATs. Hybrids 7 and 8 are recommended for higher quality environments, while hybrids 3, 5 and 12 present wide adaptability. The Lin and Binns (1988) and Annicchiarico (1992) indexes highlight the hybrid 8 as the most promising for associating high productivity and lower risk in the tested cultivation environments.

Mung bean (Vigna radiata L.) is an important edible bean in the human diet worldwide. However, its growth, development, and yield may be restricted or limited by insufficient or unbalanced nitrogen (N), phosphorus (P), and potassium (K) fertilization. Despite this, there are few long-term studies of the effects of varying levels of N, P, and K combined fertilizers and the optimal fertilization for improving mung bean yield and quality. This study was conducted to optimize the fertilization strategies for high yield and to improve yield components (pods per plant, seeds per pod, and 100-seed weight) in the Bailv9 mung bean cultivar, 23 treatments were tested in 2013–2015, using a three-factor (N, P, and K fertilizers), five-level quadratic orthogonal rotation combination design. Our studies showed that, the N, P, and K fertilizers significantly influenced the pods per plant and yield, which increased and then decreased with the increasing N, P, and K fertilizers. The 100-seed weight was significantly affected by the N and P fertilization, and it was increased consistently with the increasing N fertilizer, and decreased significantly with the increasing P fertilizer. Whereas, the seeds per pod significantly decreased with the increasing N and K fertilizers, and the P fertilizer had no significant effect on it. The NP interaction had a significant effect on yield and pods per plant at high N levels, while the NK interaction had a significant but opposite effect on yield at low N levels. The optimal fertilization conditions to obtain yield >2,141.69 kg ha-1 were 34.38–42.62 kg ha-1 N, 17.55–21.70 kg ha-1 P2O5, and 53.23–67.29 kg ha-1 K2O. Moreover, the optimal N, P, and K fertilization interval to achieve pods per plant > 23.41 and the optimal N fertilization to achieve a 100-seed weight > 6.58 g intersected with the interval for yield, but the seeds per pod did not. The fertilizer ratio for the maximum yield was N:P2O5:K2O = 1:0.5:1.59. Following three years experimentation, the optimal fertilization measures were validated in 2016–2017, the results indicated that yield increased by 19.6% than that obtained using conventional fertilization. The results of this study provide a theoretical basis and technical guidance for high-yield mung bean cultivation using the optimal fertilization measures.