Domain: Natural Science — Morphology
Target concept: Growth under nutrient-complete conditions vs. growth in potassium-deficient soil

Video generation prompt: Same seedlings were separately planted in two pots: the blue pot was filled with complete nutrient soil, and the red pot was filled with potassium-deficient soil; they were placed side by side within a few weeks, under identical light and watering conditions.

Evaluation guide:
(i) Target concept: Potassium deficiency causes specific, observable morphological impairments in seedlings under otherwise identical conditions.
Minimum mechanism: Plants require potassium for stomatal regulation and protein synthesis; its absence disrupts turgor maintenance and chlorophyll production, leading to progressive, non-reversible leaf necrosis and growth arrest, manifesting first in older leaves and at margins.
(ii)Storyline: [Frame 0–2] Side-by-side setup: blue pot (rich soil) and red pot (K-deficient soil) placed adjacent in fixed frontal view; [Frame 3–4] Identical seedlings planted into each pot (hands visible, soil undisturbed post-placement); [Frame 5–9] Static observation shot: red-pot seedling displays three co-occurring, anatomically correct deficiency signs (brown margins, older-leaf chlorosis, reduced height) while blue-pot seedling remains uniformly green, turgid, and taller; all visual evidence must be fully in-frame, frontally lit, and unobscured.

Manual:
Experimental Procedure
1. Place two identical pots side-by-side.
2. Fill blue pot with complete nutrient soil; fill red pot with potassium-deficient soil.
3. Plant one identical seedling in each pot.
4. Water both equally; place under identical light.
Observation of Experimental Phenomena
After several weeks: red-pot seedling shows stunted growth, brown leaf margins, and yellowing of older leaves; blue-pot seedling is taller, greener, with healthy leaves.
Summary of Experimental Principles
Potassium is essential for enzyme activation, osmoregulation, and stomatal function; deficiency impairs water uptake and photosynthesis, causing chlorosis, necrosis, and reduced growth.

Prompt Grounding rubric:
level_1: No blue pot or red pot appears in the frame; no seedling is visible in either pot; the pots never appear side by side in the same shot; no soil-planting action (a hand placing a seedling into soil) occurs.
level_2: Only one pot is shown, or both pots share the same color instead of one blue and one red; a seedling is missing from one or both pots; the two pots are arranged one behind the other, overlapping, or in separate shots rather than side by side; the planting action is skipped or too brief to see.
level_3: A blue pot and a red pot appear side by side in the same shot, each holding one upright seedling in soil; a planting action (a hand lowering a seedling into soil) is shown for at least one pot, though it may be brief, partially off-screen, or uneven between the two pots.
level_4: All of the score 3 requirements are met, and beyond that, both pots show clearly saturated, unmistakable blue and red hues (not muddy brown-red or grayish-blue), each seedling stands upright with its base fully visible above the soil line, the planting action into both pots is completed before the observation period, and no extra pots, seedlings, hands, or text overlays remain visible once observation begins.
level_5: All of the score 4 requirements are met, and beyond that, the soil surface of the blue pot and the soil surface of the red pot look identical to each other in color and texture throughout the video (so only pot color, not an invented soil-color difference, marks which pot received which treatment), and the camera keeps the same fixed side-by-side framing from planting through observation, with no cut, zoom, or repositioning of either pot.

Scientific and Causal Correctness rubric:
level_1: The seedling in the red pot and the seedling in the blue pot look the same in size, leaf color, and posture; none of the leaves show browning, yellowing, or stunted growth in either pot; there is no visible connection between which pot (red vs. blue) a seedling grows in and its appearance.
level_2: One seedling looks slightly different from the other, but the difference contradicts potassium deficiency: for example the red-pot (potassium-deficient) seedling looks greener or taller than the blue-pot one, or both seedlings show the same wilting/yellowing regardless of pot, or the visible symptom appears on the blue-pot (nutrient-complete) seedling instead.
level_3: The red-pot seedling shows at least one correct sign of potassium deficiency (browned/crisped leaf edges, or yellowing of its older/lower leaves, or a noticeably shorter stem than the blue-pot seedling), while the blue-pot seedling stays green, upright, and turgid; the sign is clearly visible and no contradictory symptom (e.g. unusual extra greenness) appears on the red-pot plant.
level_4: All of the score 3 requirements are met, and beyond that, the red-pot seedling shows at least two of these signs at once (browned leaf margins, yellowing concentrated in its older leaves, and reduced height compared with the blue-pot seedling), while the blue-pot seedling shows none of them; every symptom appears on the anatomically expected leaves (older leaves show the yellowing, not new growth).
level_5: All of the score 4 requirements are met, and beyond that, the red-pot seedling simultaneously shows all three signs (necrotic brown margins on at least two mature leaves, yellowing between the veins of at least two older leaves, and a visibly shorter stem than the blue-pot seedling), each one fully visible and clearly confined to the red-pot plant, while the blue-pot seedling remains deep green, upright, with fully expanded, undamaged leaves throughout.

Spatiotemporal Consistency rubric:
level_1: The blue pot or red pot jumps to a different position or vanishes between frames; a seedling changes position or angle with no visible cause; the scene abruptly switches from daylight to night or vice versa within one frame; the soil surface warps or disappears; a pot's shape breaks apart or deforms structurally.
level_2: A seedling blinks in and out of view; a pot's color noticeably shifts mid-video (e.g., blue drifting toward purple); the soil level changes for no visible reason; a shadow suddenly falls in the opposite direction with no corresponding change in a light source; the camera cuts from the side-by-side framing to a different angle (e.g., overhead or close-up) partway through.
level_3: The fixed side-by-side viewpoint is mostly held but shows slight jitter; one seedling is briefly blocked by a hand or object that is not part of the planting action; brightness flickers momentarily in a way that does not match a consistent light source; no pot vanishes, teleports, or breaks apart structurally.
level_4: All of the score 3 requirements are met, and beyond that, the side-by-side framing of the two pots is held for the entire video with no unexplained cuts, occlusions, or shape distortion; the direction and softness of the light stay the same from the planting scene through observation; shadows stay in the same position relative to each pot; any change in soil level or seedling height reflects only natural growth, never a sudden jump; no frames repeat or stutter.
level_5: All of the score 4 requirements are met, and beyond that, all motion looks physically plausible: neither seedling appears to float above its soil, leaves show a small amount of natural sway rather than perfectly rigid stillness, movement between frames looks smooth and continuous with no strobing or warping, and the edges of the pot rims and leaves stay crisp and stable rather than flickering or shimmering.